From d5d0fdf0eb340a8d6be1ccb5c57aa0363d52ef5d Mon Sep 17 00:00:00 2001
From: Greg Sjaardema <gsjaardema@gmail.com>
Date: Tue, 20 Aug 2024 16:05:07 -0600
Subject: [PATCH 1/7] SEACAS: Snapshot 2024-08-20

* APREPRO: Better parsing of strings starting with digits on command line
* Conjoin, Ejoin, EPU: Easier to specify "last N steps" on the time selection command
* NemSlice, Slice: Handle decomposition of 1D models
* IOSS: Reduce memory associated with face generation code/data
* EXODUS: Persistent redef mode to improve performance
* EXODUS: Number width routine no longer needs math functions
* IOSS: Exodus - support for lossy compression (QUANTIZE_NSD)
* IOSS: Exodus - support for additional compression algorithms
* IOSS: Initial support for better dynamic topology handling
* IOSS: Fmt support for fmt-11.X

Signed-off-by: Greg Sjaardema <gdsjaar@sandia.gov>
---
 .../seacas/applications/aprepro/aprepro.C     |   20 +-
 packages/seacas/applications/blot/linthc.blk  |    4 +-
 .../applications/cpup/CP_SystemInterface.C    |   20 +-
 .../seacas/applications/cpup/CP_Version.h     |    4 +-
 packages/seacas/applications/cpup/cpup.C      |   10 +-
 .../applications/ejoin/EJ_SystemInterface.C   |   27 +-
 .../seacas/applications/ejoin/EJ_Version.h    |    4 +-
 packages/seacas/applications/ejoin/EJoin.C    |    8 +-
 .../applications/epu/EP_SystemInterface.C     |   25 +-
 packages/seacas/applications/epu/EP_Version.h |    4 +-
 packages/seacas/applications/epu/epu.C        |    8 +-
 packages/seacas/applications/exodiff/map.C    |   24 +-
 packages/seacas/applications/nem_slice/elb.h  |    2 +-
 .../seacas/applications/nem_slice/elb_elem.C  |   32 +-
 .../applications/nem_slice/elb_loadbal.C      |  661 +++++-----
 .../applications/nem_slice/elb_output.C       |    6 +-
 .../applications/nem_spread/ps_pario_const.h  |    3 +-
 .../seacas/applications/slice/SL_Version.h    |    4 +-
 packages/seacas/applications/slice/Slice.C    |   27 +-
 packages/seacas/applications/zellij/Cell.C    |    4 +-
 packages/seacas/applications/zellij/Cell.h    |    2 +-
 .../seacas/applications/zellij/UnitCell.C     |    2 +-
 .../seacas/cmake/tpls/FindTPLADIOS2.cmake     |   90 --
 .../libraries/aprepro_lib/CMakeLists.txt      |    2 -
 .../libraries/exodus/include/exodusII.h       |   11 +-
 .../exodus/include/exodusII_cfg.h.in          |   12 +-
 .../libraries/exodus/include/exodusII_int.h   |   42 +-
 .../src/ex__put_homogenous_block_params.c     |    2 +-
 .../seacas/libraries/exodus/src/ex_add_attr.c |    2 +-
 .../seacas/libraries/exodus/src/ex_close.c    |    7 +-
 .../seacas/libraries/exodus/src/ex_conv.c     |    2 +
 .../seacas/libraries/exodus/src/ex_copy.c     |    4 +-
 .../libraries/exodus/src/ex_create_group.c    |    4 +-
 packages/seacas/libraries/exodus/src/ex_err.c |    4 +-
 .../libraries/exodus/src/ex_field_utils.c     |   13 +-
 .../exodus/src/ex_get_field_metadata.c        |   16 +-
 .../libraries/exodus/src/ex_get_group_id.c    |   11 +-
 .../seacas/libraries/exodus/src/ex_open.c     |    9 +-
 .../seacas/libraries/exodus/src/ex_open_par.c |   10 +-
 .../exodus/src/ex_put_all_var_param_ext.c     |    2 +-
 .../libraries/exodus/src/ex_put_assemblies.c  |    2 +-
 .../libraries/exodus/src/ex_put_attr_param.c  |    2 +-
 .../libraries/exodus/src/ex_put_attribute.c   |    6 +-
 .../libraries/exodus/src/ex_put_blobs.c       |    2 +-
 .../exodus/src/ex_put_block_params.c          |    2 +-
 .../libraries/exodus/src/ex_put_cmap_params.c |    2 +-
 .../exodus/src/ex_put_cmap_params_cc.c        |    2 +-
 .../exodus/src/ex_put_concat_all_blocks.c     |    2 +-
 .../exodus/src/ex_put_concat_elem_block.c     |    2 +-
 .../libraries/exodus/src/ex_put_concat_sets.c |    2 +-
 .../exodus/src/ex_put_coordinate_frames.c     |    2 +-
 .../exodus/src/ex_put_field_metadata.c        |   71 +-
 .../libraries/exodus/src/ex_put_id_map.c      |    2 +-
 .../seacas/libraries/exodus/src/ex_put_info.c |    4 +-
 .../libraries/exodus/src/ex_put_init_ext.c    |    2 +-
 .../libraries/exodus/src/ex_put_init_global.c |    2 +-
 .../libraries/exodus/src/ex_put_init_info.c   |    2 +-
 .../exodus/src/ex_put_loadbal_param.c         |    2 +-
 .../exodus/src/ex_put_loadbal_param_cc.c      |    2 +-
 .../seacas/libraries/exodus/src/ex_put_map.c  |    2 +-
 .../libraries/exodus/src/ex_put_map_param.c   |    2 +-
 .../seacas/libraries/exodus/src/ex_put_name.c |    2 +-
 .../libraries/exodus/src/ex_put_num_map.c     |    2 +-
 .../exodus/src/ex_put_partial_id_map.c        |    2 +-
 .../libraries/exodus/src/ex_put_partial_var.c |    2 +-
 .../seacas/libraries/exodus/src/ex_put_prop.c |    2 +-
 .../libraries/exodus/src/ex_put_prop_array.c  |    2 +-
 .../libraries/exodus/src/ex_put_prop_names.c  |    2 +-
 .../seacas/libraries/exodus/src/ex_put_qa.c   |    4 +-
 .../src/ex_put_reduction_variable_param.c     |    2 +-
 .../exodus/src/ex_put_reduction_vars.c        |    2 +-
 .../seacas/libraries/exodus/src/ex_put_sets.c |    2 +-
 .../libraries/exodus/src/ex_put_truth_table.c |    2 +-
 .../exodus/src/ex_put_var_multi_time.c        |    2 +-
 .../exodus/src/ex_put_variable_param.c        |    2 +-
 .../seacas/libraries/exodus/src/ex_update.c   |    9 +-
 .../seacas/libraries/exodus/src/ex_utils.c    |  121 +-
 .../seacas/libraries/exodus/test/testall.in   |    4 +-
 .../exodus/test/testwt-field-metadata.dmp     |    4 -
 .../exodus/test/testwt-field-metadata2.c      |  214 ----
 .../ioss/cmake/SEACASIoss_config.h.in         |    2 +
 .../seacas/libraries/ioss/src/CMakeLists.txt  |    9 +-
 .../ioss/src/Ioss_BasisVariableType.C         |   26 -
 .../libraries/ioss/src/Ioss_ChainGenerator.C  |   18 +-
 .../libraries/ioss/src/Ioss_CodeTypes.h       |    1 +
 .../seacas/libraries/ioss/src/Ioss_Compare.C  |    5 +
 .../libraries/ioss/src/Ioss_CopyDatabase.C    |    2 +-
 .../libraries/ioss/src/Ioss_DatabaseIO.C      |    4 +-
 .../libraries/ioss/src/Ioss_DatabaseIO.h      |   48 +-
 .../libraries/ioss/src/Ioss_Decomposition.C   |    5 +-
 .../ioss/src/Ioss_DecompositionUtils.C        |   34 +-
 .../ioss/src/Ioss_DecompositionUtils.h        |    8 +-
 .../seacas/libraries/ioss/src/Ioss_Doxygen.h  |    6 +-
 .../libraries/ioss/src/Ioss_DynamicTopology.C |  728 +++++++++++
 .../libraries/ioss/src/Ioss_DynamicTopology.h |  238 ++++
 .../libraries/ioss/src/Ioss_FaceGenerator.C   |   30 +-
 .../libraries/ioss/src/Ioss_FaceGenerator.h   |   19 +-
 .../seacas/libraries/ioss/src/Ioss_Field.C    |    1 +
 .../seacas/libraries/ioss/src/Ioss_Field.h    |   13 +
 .../seacas/libraries/ioss/src/Ioss_Glob.h     |    2 +-
 .../libraries/ioss/src/Ioss_IOFactory.C       |    4 +-
 .../libraries/ioss/src/Ioss_ParallelUtils.h   |    1 +
 .../seacas/libraries/ioss/src/Ioss_Region.C   |  406 +++++-
 .../seacas/libraries/ioss/src/Ioss_Region.h   |   65 +-
 .../libraries/ioss/src/Ioss_StructuredBlock.C |   36 +-
 .../libraries/ioss/src/Ioss_StructuredBlock.h |   12 +
 .../seacas/libraries/ioss/src/Ioss_Utils.C    |    4 +-
 .../libraries/ioss/src/Ioss_VariableType.C    |    1 +
 .../ioss/src/Ioss_ZoneConnectivity.h          |   14 +
 .../libraries/ioss/src/adios/AdiosWrapper.C   |   13 +-
 .../libraries/ioss/src/adios/AdiosWrapper.hpp |    4 +-
 .../ioss/src/adios/Ioad_DatabaseIO.h          |   24 +-
 .../ioss/src/catalyst/Iocatalyst_DatabaseIO.C |   54 +-
 .../Iocatalyst_ConduitReadTest.C              |   44 +
 .../libraries/ioss/src/cgns/Iocgns_Utils.C    |    4 +-
 .../ioss/src/exodus/Ioex_BaseDatabaseIO.C     |  276 +++-
 .../ioss/src/exodus/Ioex_BaseDatabaseIO.h     |    7 +
 .../ioss/src/exodus/Ioex_DatabaseIO.C         |   47 +-
 .../ioss/src/exodus/Ioex_ParallelDatabaseIO.C |    4 +-
 .../libraries/ioss/src/exodus/Ioex_Utils.C    |    3 +-
 .../src/exonull/Ioexnl_DecompositionData.C    |   12 +-
 .../src/exonull/Ioexnl_DecompositionData.h    |   14 +-
 .../src/faodel/Iofaodel_FieldSerialization.h  |    4 +-
 .../faodel/Iofaodel_PropertySerialization.h   |    4 +-
 .../ioss/src/init/Ionit_Initializer.C         |    9 +-
 .../seacas/libraries/ioss/src/main/io_info.C  |    8 +
 .../libraries/ioss/src/main/shell_interface.C |   26 +-
 .../seacas/libraries/ioss/src/main/skinner.C  |    2 +-
 .../seacas/libraries/ioss/src/main/sphgen.C   |    9 +-
 .../ioss/src/text_mesh/Iotm_TextMesh.C        |    1 +
 .../ioss/src/unit_tests/CMakeLists.txt        |   11 +
 .../src/unit_tests/UnitTestDynamicTopology.C  | 1111 +++++++++++++++++
 .../seacas/libraries/ioss/src/utest/Ut_ioad.C |    2 +-
 packages/seacas/scripts/exomerge3.py          |   10 +-
 134 files changed, 3996 insertions(+), 1092 deletions(-)
 delete mode 100644 packages/seacas/cmake/tpls/FindTPLADIOS2.cmake
 delete mode 100644 packages/seacas/libraries/exodus/test/testwt-field-metadata2.c
 delete mode 100644 packages/seacas/libraries/ioss/src/Ioss_BasisVariableType.C
 create mode 100644 packages/seacas/libraries/ioss/src/Ioss_DynamicTopology.C
 create mode 100644 packages/seacas/libraries/ioss/src/Ioss_DynamicTopology.h
 create mode 100644 packages/seacas/libraries/ioss/src/unit_tests/UnitTestDynamicTopology.C

diff --git a/packages/seacas/applications/aprepro/aprepro.C b/packages/seacas/applications/aprepro/aprepro.C
index 378ae87c6a23..1b74a9c00fdf 100644
--- a/packages/seacas/applications/aprepro/aprepro.C
+++ b/packages/seacas/applications/aprepro/aprepro.C
@@ -1,4 +1,4 @@
-// Copyright(C) 1999-2021, 2023 National Technology & Engineering Solutions
+// Copyright(C) 1999-2021, 2023, 2024, 2024 National Technology & Engineering Solutions
 // of Sandia, LLC (NTESS).  Under the terms of Contract DE-NA0003525 with
 // NTESS, the U.S. Government retains certain rights in this software.
 //
@@ -14,6 +14,17 @@
 
 #include "aprepro.h"
 
+namespace {
+  bool is_double(const std::string &myString)
+  {
+    std::istringstream iss(myString);
+    double             f;
+    iss >> std::noskipws >> f; // noskipws considers leading whitespace invalid
+    // Check the entire string was consumed and if either failbit or badbit is set
+    return iss.eof() && !iss.fail();
+  }
+} // namespace
+
 int main(int argc, char *argv[])
 {
   SEAMS::Aprepro           aprepro;
@@ -42,7 +53,9 @@ int main(int argc, char *argv[])
         value = value.substr(1, value.length() - 2);
         aprepro.add_variable(var, value, true); // Make it immutable
       }
-      else {
+      // See if `value` contains any characters that are invalid for a number...
+
+      else if (is_double(value)) {
         try {
           double dval = std::stod(value);
           aprepro.add_variable(var, dval, true);
@@ -58,6 +71,9 @@ int main(int argc, char *argv[])
           }
         }
       }
+      else {
+        aprepro.add_variable(var, value, true); // Make it immutable
+      }
     }
     else {
       input_files.emplace_back(argv[ai]);
diff --git a/packages/seacas/applications/blot/linthc.blk b/packages/seacas/applications/blot/linthc.blk
index 0e53deb870dd..72def06804b4 100644
--- a/packages/seacas/applications/blot/linthc.blk
+++ b/packages/seacas/applications/blot/linthc.blk
@@ -1,4 +1,4 @@
-C    Copyright(C) 1999-2020 National Technology & Engineering Solutions
+C    Copyright(C) 1999-2020, 2024 National Technology & Engineering Solutions
 C    of Sandia, LLC (NTESS).  Under the terms of Contract DE-NA0003525 with
 C    NTESS, the U.S. Government retains certain rights in this software.
 C
@@ -8,7 +8,7 @@ C    See packages/seacas/LICENSE for details
       REAL MSHBND, BLKBND, ELEBND
 C      --      Line thickness specification for lines appearing
 C      --      on mesh plots.  Specification is a real value in the
-C      --      range 0. - 1000., with 0. being the thinest line and
+C      --      range 0. - 1000., with 0. being the thinnest line and
 C      --      1000. being the thickest.
 C      -- MSHBND - Thickness of lines forming the mesh boundary.
 C      -- BLKBND - Thickness of lines forming element block boundaries.
diff --git a/packages/seacas/applications/cpup/CP_SystemInterface.C b/packages/seacas/applications/cpup/CP_SystemInterface.C
index dd9d21973134..38007c582c36 100644
--- a/packages/seacas/applications/cpup/CP_SystemInterface.C
+++ b/packages/seacas/applications/cpup/CP_SystemInterface.C
@@ -64,8 +64,12 @@ void Cpup::SystemInterface::enroll_options()
   options_.enroll("steps", GetLongOption::MandatoryValue,
                   "Specify subset of timesteps to transfer to output file.\n"
                   "\t\tFormat is beg:end:step. 1:10:2 --> 1,3,5,7,9\n"
+                  "\t\tIf the 'beg' or 'end' is < 0, then it is the \"-Nth\" step...\n"
+                  "\t\t-1 is \"first last\" or last, -3 is \"third last\"\n"
+                  "\t\tTo copy just the last 3 steps, do: `-steps -3:-1`\n"
                   "\t\tEnter LAST for last step",
                   "1:", nullptr, true);
+
   options_.enroll("extension", GetLongOption::MandatoryValue,
                   "CGNS database extension for the input files", "cgns");
 
@@ -466,7 +470,11 @@ void Cpup::SystemInterface::parse_step_option(const char *tokens)
   //:    <li>":Y"                 -- 1 to Y by 1</li>
   //:    <li>"::Z"                -- 1 to oo by Z</li>
   //:  </ul>
-  //: The count and step must always be >= 0
+  //: The step must always be > 0
+  //: If the 'from' or 'to' is < 0, then it is the "-Nth" step...
+  //: -1 is "first last" or last
+  //: -4 is "fourth last step"
+  //: To copy just the last 3 steps, do: `-steps -3:-1`
 
   // Break into tokens separated by ":"
 
@@ -482,24 +490,24 @@ void Cpup::SystemInterface::parse_step_option(const char *tokens)
       for (auto &val : vals) {
         // Parse 'i'th field
         char tmp_str[128];
-        int  k = 0;
 
+        int k = 0;
         while (tokens[j] != '\0' && tokens[j] != ':') {
           tmp_str[k++] = tokens[j++];
         }
 
         tmp_str[k] = '\0';
         if (strlen(tmp_str) > 0) {
-          val = strtoul(tmp_str, nullptr, 0);
+          val = strtol(tmp_str, nullptr, 0);
         }
 
         if (tokens[j++] == '\0') {
           break; // Reached end of string
         }
       }
-      stepMin_      = abs(vals[0]);
-      stepMax_      = abs(vals[1]);
-      stepInterval_ = abs(vals[2]);
+      stepMin_      = vals[0];
+      stepMax_      = vals[1];
+      stepInterval_ = abs(vals[2]); // step is always positive...
     }
     else if (str_equal("LAST", tokens)) {
       stepMin_ = stepMax_ = -1;
diff --git a/packages/seacas/applications/cpup/CP_Version.h b/packages/seacas/applications/cpup/CP_Version.h
index 8ba908eaf3a6..9ddb0b5d1402 100644
--- a/packages/seacas/applications/cpup/CP_Version.h
+++ b/packages/seacas/applications/cpup/CP_Version.h
@@ -1,5 +1,5 @@
 /*
- * Copyright(C) 1999-2023 National Technology & Engineering Solutions
+ * Copyright(C) 1999-2024 National Technology & Engineering Solutions
  * of Sandia, LLC (NTESS).  Under the terms of Contract DE-NA0003525 with
  * NTESS, the U.S. Government retains certain rights in this software.
  *
@@ -8,4 +8,4 @@
 #pragma once
 #include <array>
 #include <string>
-static const std::array<std::string, 3> qainfo{"cpup", "0.95 beta", "2023/04/25"};
+static const std::array<std::string, 3> qainfo{"cpup", "0.96 beta", "2024/08/06"};
diff --git a/packages/seacas/applications/cpup/cpup.C b/packages/seacas/applications/cpup/cpup.C
index a382b488ca50..c88c46703bda 100644
--- a/packages/seacas/applications/cpup/cpup.C
+++ b/packages/seacas/applications/cpup/cpup.C
@@ -1,4 +1,4 @@
-// Copyright(C) 1999-2023 National Technology & Engineering Solutions
+// Copyright(C) 1999-2024 National Technology & Engineering Solutions
 // of Sandia, LLC (NTESS).  Under the terms of Contract DE-NA0003525 with
 // NTESS, the U.S. Government retains certain rights in this software.
 //
@@ -406,9 +406,11 @@ template <typename INT> void cpup(Cpup::SystemInterface &interFace, INT /*dummy*
   int ts_max  = interFace.step_max();
   int ts_step = interFace.step_interval();
 
-  if (ts_min == -1 && ts_max == -1) {
-    ts_min = num_time_steps;
-    ts_max = num_time_steps;
+  if (ts_min < 0) {
+    ts_min = num_time_steps + 1 + ts_min;
+  }
+  if (ts_max < 0) {
+    ts_max = num_time_steps + 1 + ts_max;
   }
 
   // Time steps for output file
diff --git a/packages/seacas/applications/ejoin/EJ_SystemInterface.C b/packages/seacas/applications/ejoin/EJ_SystemInterface.C
index a551af6ced4d..f1aeecd6d920 100644
--- a/packages/seacas/applications/ejoin/EJ_SystemInterface.C
+++ b/packages/seacas/applications/ejoin/EJ_SystemInterface.C
@@ -143,8 +143,11 @@ void SystemInterface::enroll_options()
   options_.enroll("steps", GetLongOption::MandatoryValue,
                   "Specify subset of timesteps to transfer to output file.\n"
                   "\t\tFormat is beg:end:step. 1:10:2 --> 1,3,5,7,9\n"
-                  "\t\tTo only transfer last step, use '-steps LAST'",
-                  "1:");
+                  "\t\tIf the 'beg' or 'end' is < 0, then it is the \"-Nth\" step...\n"
+                  "\t\t-1 is \"first last\" or last, -3 is \"third last\"\n"
+                  "\t\tTo copy just the last 3 steps, do: `-steps -3:-1`\n"
+                  "\t\tEnter LAST for last step",
+                  "1:", nullptr, true);
 
   options_.enroll("gvar", GetLongOption::MandatoryValue,
                   "Comma-separated list of global variables to be joined or ALL or NONE.", nullptr);
@@ -478,15 +481,17 @@ void SystemInterface::parse_step_option(const char *tokens)
   //: The defined formats for the count attribute are:<br>
   //:  <ul>
   //:    <li><missing> -- default -- 1 <= count <= oo  (all steps)</li>
-  //:    <li>"X"                  -- X <= count <= X  (just step X). If X == LAST, last step
-  // only</li>
+  //:    <li>"X"                  -- X <= count <= X  (just step X) LAST for last step.</li>
   //:    <li>"X:Y"                -- X to Y by 1</li>
   //:    <li>"X:"                 -- X to oo by 1</li>
   //:    <li>":Y"                 -- 1 to Y by 1</li>
   //:    <li>"::Z"                -- 1 to oo by Z</li>
-  //:    <li>"LAST"               -- last step only</li>
   //:  </ul>
-  //: The count and step must always be >= 0
+  //: The step must always be > 0
+  //: If the 'from' or 'to' is < 0, then it is the "-Nth" step...
+  //: -1 is "first last" or last
+  //: -4 is "fourth last step"
+  //: To copy just the last 3 steps, do: `-steps -3:-1`
 
   // Break into tokens separated by ":"
 
@@ -502,24 +507,24 @@ void SystemInterface::parse_step_option(const char *tokens)
       for (auto &val : vals) {
         // Parse 'i'th field
         char tmp_str[128];
-        int  k = 0;
 
+        int k = 0;
         while (tokens[j] != '\0' && tokens[j] != ':') {
           tmp_str[k++] = tokens[j++];
         }
 
         tmp_str[k] = '\0';
         if (strlen(tmp_str) > 0) {
-          val = strtoul(tmp_str, nullptr, 0);
+          val = strtol(tmp_str, nullptr, 0);
         }
 
         if (tokens[j++] == '\0') {
           break; // Reached end of string
         }
       }
-      stepMin_      = abs(vals[0]);
-      stepMax_      = abs(vals[1]);
-      stepInterval_ = abs(vals[2]);
+      stepMin_      = vals[0];
+      stepMax_      = vals[1];
+      stepInterval_ = abs(vals[2]); // step is always positive...
     }
     else if (str_equal("LAST", tokens)) {
       stepMin_ = stepMax_ = -1;
diff --git a/packages/seacas/applications/ejoin/EJ_Version.h b/packages/seacas/applications/ejoin/EJ_Version.h
index 8fad82651f41..9389859444c1 100644
--- a/packages/seacas/applications/ejoin/EJ_Version.h
+++ b/packages/seacas/applications/ejoin/EJ_Version.h
@@ -9,6 +9,6 @@
 
 static const std::array<std::string, 3> qainfo{
     "ejoin",
-    "2024/02/21",
-    "1.6.3",
+    "2024/08/06",
+    "1.6.4",
 };
diff --git a/packages/seacas/applications/ejoin/EJoin.C b/packages/seacas/applications/ejoin/EJoin.C
index ef15d73cc1c3..8cbbe7315c41 100644
--- a/packages/seacas/applications/ejoin/EJoin.C
+++ b/packages/seacas/applications/ejoin/EJoin.C
@@ -528,9 +528,11 @@ double ejoin(SystemInterface &interFace, std::vector<Ioss::Region *> &part_mesh,
   int ts_step   = interFace.step_interval();
   int num_steps = static_cast<int>(global_times.size());
 
-  if (ts_min == -1 && ts_max == -1) {
-    ts_min = num_steps;
-    ts_max = num_steps;
+  if (ts_min < 0) {
+    ts_min = num_steps + 1 + ts_min;
+  }
+  if (ts_max < 0) {
+    ts_max = num_steps + 1 + ts_max;
   }
   ts_max = ts_max < num_steps ? ts_max : num_steps;
 
diff --git a/packages/seacas/applications/epu/EP_SystemInterface.C b/packages/seacas/applications/epu/EP_SystemInterface.C
index 21ff8d183e3c..ca97eb217f02 100644
--- a/packages/seacas/applications/epu/EP_SystemInterface.C
+++ b/packages/seacas/applications/epu/EP_SystemInterface.C
@@ -175,6 +175,9 @@ void Excn::SystemInterface::enroll_options()
   options_.enroll("steps", GetLongOption::MandatoryValue,
                   "Specify subset of timesteps to transfer to output file.\n"
                   "\t\tFormat is beg:end:step. 1:10:2 --> 1,3,5,7,9\n"
+                  "\t\tIf the 'beg' or 'end' is < 0, then it is the \"-Nth\" step...\n"
+                  "\t\t-1 is \"first last\" or last, -3 is \"third last\"\n"
+                  "\t\tTo copy just the last 3 steps, do: `-steps -3:-1`\n"
                   "\t\tEnter LAST for last step",
                   "1:", nullptr, true);
 
@@ -545,7 +548,11 @@ void Excn::SystemInterface::parse_step_option(const char *tokens)
   //:    <li>":Y"                 -- 1 to Y by 1</li>
   //:    <li>"::Z"                -- 1 to oo by Z</li>
   //:  </ul>
-  //: The count and step must always be >= 0
+  //: The step must always be > 0
+  //: If the 'from' or 'to' is < 0, then it is the "-Nth" step...
+  //: -1 is "first last" or last
+  //: -4 is "fourth last step"
+  //: To copy just the last 3 steps, do: `-steps -3:-1`
 
   // Break into tokens separated by ":"
 
@@ -555,34 +562,30 @@ void Excn::SystemInterface::parse_step_option(const char *tokens)
     if (strchr(tokens, ':') != nullptr) {
       // The string contains a separator
 
-      int vals[3];
-      vals[0] = stepMin_;
-      vals[1] = stepMax_;
-      vals[2] = stepInterval_;
+      std::array<int, 3> vals{stepMin_, stepMax_, stepInterval_};
 
       int j = 0;
       for (auto &val : vals) {
         // Parse 'i'th field
         char tmp_str[128];
-        ;
-        int k = 0;
 
+        int k = 0;
         while (tokens[j] != '\0' && tokens[j] != ':') {
           tmp_str[k++] = tokens[j++];
         }
 
         tmp_str[k] = '\0';
         if (strlen(tmp_str) > 0) {
-          val = strtoul(tmp_str, nullptr, 0);
+          val = strtol(tmp_str, nullptr, 0);
         }
 
         if (tokens[j++] == '\0') {
           break; // Reached end of string
         }
       }
-      stepMin_      = abs(vals[0]);
-      stepMax_      = abs(vals[1]);
-      stepInterval_ = abs(vals[2]);
+      stepMin_      = vals[0];
+      stepMax_      = vals[1];
+      stepInterval_ = abs(vals[2]); // step is always positive...
     }
     else if (str_equal("LAST", tokens)) {
       stepMin_ = stepMax_ = -1;
diff --git a/packages/seacas/applications/epu/EP_Version.h b/packages/seacas/applications/epu/EP_Version.h
index aca0e9ff6557..44cabbaaa476 100644
--- a/packages/seacas/applications/epu/EP_Version.h
+++ b/packages/seacas/applications/epu/EP_Version.h
@@ -11,6 +11,6 @@
 
 static const std::array<std::string, 3> qainfo{
     "epu --  E Pluribus Unum",
-    "6.09",
-    "2024/04/18",
+    "6.10",
+    "2024/08/06",
 };
diff --git a/packages/seacas/applications/epu/epu.C b/packages/seacas/applications/epu/epu.C
index 89fcb8cf97c9..30a11cefd1a1 100644
--- a/packages/seacas/applications/epu/epu.C
+++ b/packages/seacas/applications/epu/epu.C
@@ -1325,9 +1325,11 @@ int epu(SystemInterface &interFace, int start_part, int part_count, int cycle, T
   int ts_max  = interFace.step_max();
   int ts_step = interFace.step_interval();
 
-  if (ts_min == -1 && ts_max == -1) {
-    ts_min = num_time_steps;
-    ts_max = num_time_steps;
+  if (ts_min < 0) {
+    ts_min = num_time_steps + 1 + ts_min;
+  }
+  if (ts_max < 0) {
+    ts_max = num_time_steps + 1 + ts_max;
   }
 
   // Time steps for output file
diff --git a/packages/seacas/applications/exodiff/map.C b/packages/seacas/applications/exodiff/map.C
index 69b1fbae44de..62b872ccc7c5 100644
--- a/packages/seacas/applications/exodiff/map.C
+++ b/packages/seacas/applications/exodiff/map.C
@@ -1,4 +1,4 @@
-// Copyright(C) 1999-2023 National Technology & Engineering Solutions
+// Copyright(C) 1999-2024 National Technology & Engineering Solutions
 // of Sandia, LLC (NTESS).  Under the terms of Contract DE-NA0003525 with
 // NTESS, the U.S. Government retains certain rights in this software.
 //
@@ -23,9 +23,9 @@ namespace {
   double find_range(const double *x, size_t num_nodes);
 
   template <typename INT>
-  INT Find(double x0, double y0, double z0, const std::vector<double> &x,
-           const std::vector<double> &y, const std::vector<double> &z, const std::vector<INT> &id,
-           int dim, bool ignore_dups);
+  int64_t Find(double x0, double y0, double z0, const std::vector<double> &x,
+               const std::vector<double> &y, const std::vector<double> &z,
+               const std::vector<INT> &id, int dim, bool ignore_dups);
 
   template <typename INT>
   void Compute_Node_Map(std::vector<INT> &node_map, ExoII_Read<INT> &file1, ExoII_Read<INT> &file2);
@@ -164,7 +164,7 @@ void Compute_Maps(std::vector<INT> &node_map, std::vector<INT> &elmt_map, ExoII_
       }
 
       // Locate midpoint in sorted array.
-      INT sort_idx = Find(mid_x, mid_y, mid_z, x2, y2, z2, id, dim, interFace.ignore_dups);
+      int64_t sort_idx = Find(mid_x, mid_y, mid_z, x2, y2, z2, id, dim, interFace.ignore_dups);
 
       if (sort_idx < 0) {
         Error(fmt::format("Files are different (couldn't match element {} from block {} from first "
@@ -457,7 +457,7 @@ void Compute_Partial_Maps(std::vector<INT> &node_map, std::vector<INT> &elmt_map
       }
 
       // Locate midpoint in sorted array.
-      INT sort_idx = Find(mid_x, mid_y, mid_z, x2, y2, z2, id2, dim, interFace.ignore_dups);
+      int64_t sort_idx = Find(mid_x, mid_y, mid_z, x2, y2, z2, id2, dim, interFace.ignore_dups);
       if (sort_idx < 0) {
         unmatched++;
         if (first && interFace.show_unmatched) {
@@ -826,9 +826,9 @@ namespace {
   }
 
   template <typename INT>
-  INT Find(double x0, double y0, double z0, const std::vector<double> &x,
-           const std::vector<double> &y, const std::vector<double> &z, const std::vector<INT> &id,
-           int dim, bool ignore_dups)
+  int64_t Find(double x0, double y0, double z0, const std::vector<double> &x,
+               const std::vector<double> &y, const std::vector<double> &z,
+               const std::vector<INT> &id, int dim, bool ignore_dups)
   {
     if (x.empty()) {
       return -1;
@@ -856,7 +856,7 @@ namespace {
       }
     }
 
-    INT i = low == N ? N - 1 : low; // Make sure index falls within array bounds.
+    int64_t i = low == N ? N - 1 : low; // Make sure index falls within array bounds.
 
     if (i == 0 && interFace.coord_tol.Diff(x[id[i]], x0)) {
       // Could not find an index within tolerance on x coordinate.
@@ -871,7 +871,7 @@ namespace {
     // Search until tolerance between the x coordinate fails or a match is found.
     // If a match is found, the loop continues in order to check for dups.
 
-    INT index = -1;
+    int64_t index = -1;
     do {
       if (dim == 1 || (dim == 2 && !interFace.coord_tol.Diff(y[id[i]], y0)) ||
           (dim == 3 && !interFace.coord_tol.Diff(y[id[i]], y0) &&
@@ -900,7 +900,7 @@ namespace {
 
         index = i;
       }
-    } while (++i < (INT)N && !interFace.coord_tol.Diff(x[id[i]], x0));
+    } while (++i < (int64_t)N && !interFace.coord_tol.Diff(x[id[i]], x0));
 
     interFace.coord_tol.type = save_tolerance_type;
     return index;
diff --git a/packages/seacas/applications/nem_slice/elb.h b/packages/seacas/applications/nem_slice/elb.h
index 815c873e6514..6255820f5106 100644
--- a/packages/seacas/applications/nem_slice/elb.h
+++ b/packages/seacas/applications/nem_slice/elb.h
@@ -14,7 +14,7 @@
 #include <string>
 #include <vector>
 
-#define ELB_VERSION "5.00"
+#define ELB_VERSION "5.04 (2024/08/19)"
 #define UTIL_NAME   "nem_slice"
 #define ELB_FALSE   0
 #define ELB_TRUE    1
diff --git a/packages/seacas/applications/nem_slice/elb_elem.C b/packages/seacas/applications/nem_slice/elb_elem.C
index cd56ccc4d82e..f706c25dee7b 100644
--- a/packages/seacas/applications/nem_slice/elb_elem.C
+++ b/packages/seacas/applications/nem_slice/elb_elem.C
@@ -326,8 +326,8 @@ int get_elem_info(const int req, const E_Type etype)
   case BAR2:
     switch (req) {
     case NNODES: answer = 2; break;
-    case NSIDE_NODES: answer = 2; break;
-    case NSIDES: answer = 1; break;
+    case NSIDE_NODES: answer = 1; break;
+    case NSIDES: answer = 2; break;
     case NDIM: /* number of physical dimensions */ answer = 1; break;
     default:
       Gen_Error(0, "fatal: unknown quantity");
@@ -365,8 +365,8 @@ int get_elem_info(const int req, const E_Type etype)
   case BAR3:
     switch (req) {
     case NNODES: answer = 3; break;
-    case NSIDE_NODES: answer = 2; break;
-    case NSIDES: answer = 1; break;
+    case NSIDE_NODES: answer = 1; break;
+    case NSIDES: answer = 2; break;
     case NDIM: /* number of physical dimensions */ answer = 1; break;
     default:
       Gen_Error(0, "fatal: unknown quantity");
@@ -945,6 +945,15 @@ int get_side_id(const E_Type etype, const INT *connect, const int nsnodes, INT s
   switch (etype) {
   case BAR2:
   case BAR3:
+    /* SIDE 1 */
+    if (side_nodes[0] == connect[0]) {
+      return 1;
+    }
+    if (side_nodes[0] == connect[1]) {
+      return 2;
+    }
+    break;
+
   case SHELL2:
   case SHELL3:
     /* SIDE 1 */
@@ -1661,26 +1670,33 @@ int ss_to_node_list(const E_Type etype,    /* The element type */
       {1, 4, 3, 2, 9, 8, 7, 6, 14}    // side 5 (quad)
   };
 
-  static int bar_table[1][3] = {{1, 2, 3}};
+  static int shell_bar_table[1][3] = {{1, 2, 3}};
+  static int bar_table[2][1]       = {{1}, {2}};
 
   /* Locally decrement side_num */
   side_num--;
 
   /* Switch over the element type. */
   switch (etype) {
+  case BAR3:
   case BAR2:
+    /* Bar1 has 2 sides, each is a single node */
+    for (i = 0; i < 1; i++) {
+      ss_node_list[i] = connect[(bar_table[side_num][i] - 1)];
+    }
+    break;
+
   case SHELL2:
     /* Bar1 has 1 side */
     for (i = 0; i < 2; i++) {
-      ss_node_list[i] = connect[(bar_table[side_num][i] - 1)];
+      ss_node_list[i] = connect[(shell_bar_table[side_num][i] - 1)];
     }
     break;
 
-  case BAR3:
   case SHELL3:
     /* Bar has 1 side */
     for (i = 0; i < 3; i++) {
-      ss_node_list[i] = connect[(bar_table[side_num][i] - 1)];
+      ss_node_list[i] = connect[(shell_bar_table[side_num][i] - 1)];
     }
     break;
 
diff --git a/packages/seacas/applications/nem_slice/elb_loadbal.C b/packages/seacas/applications/nem_slice/elb_loadbal.C
index 0d65ba204a41..2b42dbd5b5cf 100644
--- a/packages/seacas/applications/nem_slice/elb_loadbal.C
+++ b/packages/seacas/applications/nem_slice/elb_loadbal.C
@@ -1535,358 +1535,435 @@ namespace {
     /* Find the internal and border elements */
     double time1 = get_time();
 
-    for (size_t ecnt = 0; ecnt < mesh->num_elems; ecnt++) {
-      int proc = lb->vertex2proc[ecnt];
-      assert(proc < machine->num_procs);
-      bool   internal = true;
-      int    flag     = 0;
-      E_Type etype    = mesh->elem_type[ecnt];
-      int    dim1     = get_elem_info(NDIM, etype);
-
-      /* need to check for hex's or tet's */
-      hflag1 = is_hex(etype);
+    int mesh_dim = mesh->num_dims;
+    if (mesh_dim == 1) {
+      std::vector<int> categorized(mesh->num_elems);
+      for (size_t ecnt = 0; ecnt < mesh->num_elems; ecnt++) {
+        int  proce  = lb->vertex2proc[ecnt];
+        auto etype  = mesh->elem_type[ecnt];
+        int  nsides = get_elem_info(NSIDES, etype);
+        assert(nsides == 2);
+
+        /* check each side of this element */
+        for (int nscnt = 0; nscnt < nsides; nscnt++) {
+
+          /* get the node on this element side (should only be one)*/
+          side_cnt = ss_to_node_list(etype, mesh->connect[ecnt], (nscnt + 1), side_nodes);
+          assert(side_cnt == 1);
+
+          size_t nhold = graph->sur_elem[side_nodes[0]].size();
+          assert(nhold == 1 || nhold == 2);
+          if (nhold == 2) {
+            // 2 elements connected to this node -- `ecnt` and the other one...
+            for (size_t ncnt = 0; ncnt < nhold; ncnt++) {
+              size_t elem = graph->sur_elem[side_nodes[0]][ncnt];
+              if (elem == ecnt) {
+                continue;
+              }
+              int proc2 = lb->vertex2proc[elem];
+              if (proce == proc2) {
+                continue;
+              }
+              else {
+                // Processors of the two elements are different, so we are
+                // at a processor boundary...
+                if (!categorized[ecnt]) {
+                  lb->bor_elems[proce].push_back(ecnt);
+                  categorized[ecnt] = 1;
+                }
+                lb->e_cmap_elems[proc2].push_back(elem);
+                lb->e_cmap_sides[proc2].push_back(2 - ncnt);
+                lb->e_cmap_procs[proc2].push_back(proce);
+                lb->e_cmap_neigh[proc2].push_back(ecnt);
+              }
+            }
+          }
+        }
+        if (!categorized[ecnt]) {
+          lb->int_elems[proce].push_back(ecnt);
+          categorized[ecnt] = 1;
+        }
+      }
+    }
+    else {
+      for (size_t ecnt = 0; ecnt < mesh->num_elems; ecnt++) {
+        int proc = lb->vertex2proc[ecnt];
+        assert(proc < machine->num_procs);
+        bool internal = true;
+        int  flag     = 0;
+        auto etype    = mesh->elem_type[ecnt];
+        int  dim1     = get_elem_info(NDIM, etype);
 
-      /* a TET10 cannot connect to a HEX */
-      tflag1 = is_tet(etype);
+        /* need to check for hex's or tet's */
+        hflag1 = is_hex(etype);
 
-      int nsides = get_elem_info(NSIDES, etype);
+        /* a tet10 cannot connect to a hex */
+        tflag1 = is_tet(etype);
 
-      /* check each side of this element */
-      for (int nscnt = 0; nscnt < nsides; nscnt++) {
+        int nsides = get_elem_info(NSIDES, etype);
 
-        /* get the list of nodes on this element side */
-        side_cnt = ss_to_node_list(etype, mesh->connect[ecnt], (nscnt + 1), side_nodes);
+        /* check each side of this element */
+        for (int nscnt = 0; nscnt < nsides; nscnt++) {
 
-        /*
-         * now determine how many side set nodes are needed to
-         * determine if there is an element connected to this side.
-         *
-         * 2-D - need two nodes, so find one intersection
-         * 3-D - need three nodes, so find two intersections
-         * NOTE: must check to make sure that this number is not
-         *       larger than the number of nodes on the sides (ie - SHELL).
-         */
+          /* get the list of nodes on this element side */
+          side_cnt = ss_to_node_list(etype, mesh->connect[ecnt], (nscnt + 1), side_nodes);
 
-        int nnodes = mesh->num_dims;
-        if (side_cnt < nnodes) {
-          nnodes = side_cnt;
-        }
-        nnodes--; /* decrement to find the number of intersections needed */
+          /*
+           * now determine how many side set nodes are needed to
+           * determine if there is an element connected to this side.
+           *
+           * 1-d - need one node
+           * 2-d - need two nodes, so find one intersection
+           * 3-d - need three nodes, so find two intersections
+           * note: must check to make sure that this number is not
+           *       larger than the number of nodes on the sides (ie - shell).
+           */
 
-        nelem = 0; /* reset this in case no intersections are needed */
+          int nnodes = mesh->num_dims;
+          if (side_cnt < nnodes) {
+            nnodes = side_cnt;
+          }
+          if (nnodes > 1)
+            nnodes--; /* decrement to find the number of intersections needed */
 
-        /*
-         * need to handle hex's differently because of
-         * the tet/hex combination
-         */
+          nelem = 0; /* reset this in case no intersections are needed */
 
-        if (!hflag1) { /* Not a hex */
+          /*
+           * need to handle hex's differently because of
+           * the tet/hex combination
+           */
 
-          /* ignore degenerate bars */
+          if (!hflag1) { /* not a hex */
 
-          if (!((etype == BAR2 || etype == SHELL2) && side_nodes[0] == side_nodes[1])) {
+            if (etype == BAR2 || etype == BAR3) {
+              size_t nhold = graph->sur_elem[side_nodes[0]].size();
+              if (nhold > 1) {
+                for (size_t ncnt = 0; ncnt < nhold; ncnt++) {
+                  hold_elem[ncnt] = graph->sur_elem[side_nodes[0]][ncnt];
+                }
 
-            size_t nhold = graph->sur_elem[side_nodes[0]].size();
-            for (size_t ncnt = 0; ncnt < nhold; ncnt++) {
-              hold_elem[ncnt] = graph->sur_elem[side_nodes[0]][ncnt];
-            }
+                for (int ncnt = 0; ncnt < nnodes; ncnt++) {
+                  /* Find elements connected to both node '0' and node 'ncnt+1' */
+                  nelem = find_inter(Data(hold_elem), Data(graph->sur_elem[side_nodes[(ncnt + 1)]]),
+                                     nhold, graph->sur_elem[side_nodes[(ncnt + 1)]].size(),
+                                     Data(pt_list));
 
-            for (int ncnt = 0; ncnt < nnodes; ncnt++) {
-              /* Find elements connected to both node '0' and node 'ncnt+1' */
-              nelem =
-                  find_inter(Data(hold_elem), Data(graph->sur_elem[side_nodes[(ncnt + 1)]]), nhold,
-                             graph->sur_elem[side_nodes[(ncnt + 1)]].size(), Data(pt_list));
+                  if (nelem < 2) {
+                    break;
+                  }
 
-              if (nelem < 2) {
-                break;
+                  nhold = nelem;
+                  for (int ncnt2 = 0; ncnt2 < nelem; ncnt2++) {
+                    hold_elem[ncnt2] = hold_elem[pt_list[ncnt2]];
+                  }
+                }
               }
+            }
+            else if (!((etype == BAR2 || etype == SHELL2) && side_nodes[0] == side_nodes[1])) {
 
-              nhold = nelem;
-              for (int ncnt2 = 0; ncnt2 < nelem; ncnt2++) {
-                hold_elem[ncnt2] = hold_elem[pt_list[ncnt2]];
+              size_t nhold = graph->sur_elem[side_nodes[0]].size();
+              for (size_t ncnt = 0; ncnt < nhold; ncnt++) {
+                hold_elem[ncnt] = graph->sur_elem[side_nodes[0]][ncnt];
               }
-            }
-          }
-          else {
-            fmt::print("WARNING: Element = {} is a DEGENERATE BAR\n", ecnt + 1);
-          }
-        }
-        else { /* Is a hex */
 
-          /*
-           * Hex faces are fairly complicated now. There are two
-           * exceptions to the standard case:
-           *   1. it is a degenerate hex (mimics a wedge). this has
-           *      two special faces, the first is a triangle, and the
-           *      second is a 2d line
-           *   2. two tets are connected to this hex face
-           */
+              for (int ncnt = 0; ncnt < nnodes; ncnt++) {
+                /* Find elements connected to both node '0' and node 'ncnt+1' */
+                nelem = find_inter(Data(hold_elem), Data(graph->sur_elem[side_nodes[(ncnt + 1)]]),
+                                   nhold, graph->sur_elem[side_nodes[(ncnt + 1)]].size(),
+                                   Data(pt_list));
 
-          /* first need to check for a degenerate element */
-          dflag = 0;
-          if (side_nodes[0] == side_nodes[1] || side_nodes[0] == side_nodes[3]) {
-            dflag++;
-          }
-          if (side_nodes[2] == side_nodes[1] || side_nodes[2] == side_nodes[3]) {
-            dflag++;
-          }
+                if (nelem < 2) {
+                  break;
+                }
 
-          /*
-           * if both flags are set, then this face is the 2d line,
-           * and should be ignored with respect to elemental
-           * communication maps
-           */
-          if (dflag == 2) {
-            nelem = 1;
+                nhold = nelem;
+                for (int ncnt2 = 0; ncnt2 < nelem; ncnt2++) {
+                  hold_elem[ncnt2] = hold_elem[pt_list[ncnt2]];
+                }
+              }
+            }
+            else {
+              fmt::print("WARNING: Element = {} is a DEGENERATE BAR\n", ecnt + 1);
+            }
           }
-          else {
+          else { /* Is a hex */
+
             /*
-             * In order to check for two tets connected to this face,
-             * check the intersection of opposite corners of this face.
-             * Both tets should show up in the intersection of one of the
-             * sets of opposite corners (nothing should show up in the
-             * other).
+             * Hex faces are fairly complicated now. There are two
+             * exceptions to the standard case:
+             *   1. it is a degenerate hex (mimics a wedge). this has
+             *      two special faces, the first is a triangle, and the
+             *      second is a 2d line
+             *   2. two tets are connected to this hex face
              */
 
+            /* first need to check for a degenerate element */
+            dflag = 0;
+            if (side_nodes[0] == side_nodes[1] || side_nodes[0] == side_nodes[3]) {
+              dflag++;
+            }
+            if (side_nodes[2] == side_nodes[1] || side_nodes[2] == side_nodes[3]) {
+              dflag++;
+            }
+
             /*
-             * Initial check is side nodes 0 and 2 which are
-             * diagonally opposite
+             * if both flags are set, then this face is the 2d line,
+             * and should be ignored with respect to elemental
+             * communication maps
              */
-            int    inode = 0;
-            int    node  = 2;
-            size_t nhold = 0;
-            for (int ncnt = 0; ncnt < nnodes; ncnt++) {
-              /* Find elements connected to both node 'inode' and node 'node' */
-              nelem = find_inter(Data(graph->sur_elem[side_nodes[inode]]),
-                                 Data(graph->sur_elem[side_nodes[node]]),
-                                 graph->sur_elem[side_nodes[inode]].size(),
-                                 graph->sur_elem[side_nodes[node]].size(), Data(pt_list));
-
-              if (nelem > 1) {
-                if (ncnt == 0) {
-                  nhold = nelem;
-                  for (int ncnt2 = 0; ncnt2 < nelem; ncnt2++) {
-                    hold_elem[ncnt2] = graph->sur_elem[side_nodes[inode]][pt_list[ncnt2]];
-                  }
+            if (dflag == 2) {
+              nelem = 1;
+            }
+            else {
+              /*
+               * In order to check for two tets connected to this face,
+               * check the intersection of opposite corners of this face.
+               * Both tets should show up in the intersection of one of the
+               * sets of opposite corners (nothing should show up in the
+               * other).
+               */
 
-                  if (dflag) {
-                    /*
-                     * in this case, need to get an intersection with
-                     * another (unique) point since nodes 0 and 2
-                     * may represent an edge and not the diagonal
-                     */
-                    if (side_nodes[1] != side_nodes[0] && side_nodes[1] != side_nodes[2]) {
-                      node = 1;
+              /*
+               * Initial check is side nodes 0 and 2 which are
+               * diagonally opposite
+               */
+              int    inode = 0;
+              int    node  = 2;
+              size_t nhold = 0;
+              for (int ncnt = 0; ncnt < nnodes; ncnt++) {
+                /* Find elements connected to both node 'inode' and node 'node' */
+                nelem = find_inter(Data(graph->sur_elem[side_nodes[inode]]),
+                                   Data(graph->sur_elem[side_nodes[node]]),
+                                   graph->sur_elem[side_nodes[inode]].size(),
+                                   graph->sur_elem[side_nodes[node]].size(), Data(pt_list));
+
+                if (nelem > 1) {
+                  if (ncnt == 0) {
+                    nhold = nelem;
+                    for (int ncnt2 = 0; ncnt2 < nelem; ncnt2++) {
+                      hold_elem[ncnt2] = graph->sur_elem[side_nodes[inode]][pt_list[ncnt2]];
+                    }
+
+                    if (dflag) {
+                      /*
+                       * in this case, need to get an intersection with
+                       * another (unique) point since nodes 0 and 2
+                       * may represent an edge and not the diagonal
+                       */
+                      if (side_nodes[1] != side_nodes[0] && side_nodes[1] != side_nodes[2]) {
+                        node = 1;
+                      }
+                      else {
+                        node = 3;
+                      }
                     }
                     else {
-                      node = 3;
+                      /*
+                       * in the non-degenerate case, if an element is connected
+                       * to two opposite nodes, then it must share a face.
+                       */
+                      break;
                     }
                   }
                   else {
-                    /*
-                     * in the non-degenerate case, if an element is connected
-                     * to two opposite nodes, then it must share a face.
-                     */
-                    break;
-                  }
-                }
-                else {
-                  /* This is the second or later time through this
-                     loop and each time through, there have been two
-                     or more elements that are connected to 'node'
-                     (which changes) and 'inode'.  We want to make
-                     sure that the elements matched this time through
-                     were also in the list the first time through so
-                     that the elements contain nodes 0 1 2 of the face
-                     and not just 0 1 and 0 2...
-                     So, this time, only put an element in the list if
-                     it was in the list before.
-                  */
-                  for (size_t ncnt2 = 0; ncnt2 < nhold; ncnt2++) {
-                    hold_elem[ncnt2] = -hold_elem[ncnt2];
-                  }
-                  for (int ncnt3 = 0; ncnt3 < nelem; ncnt3++) {
+                    /* This is the second or later time through this
+                       loop and each time through, there have been two
+                       or more elements that are connected to 'node'
+                       (which changes) and 'inode'.  We want to make
+                       sure that the elements matched this time through
+                       were also in the list the first time through so
+                       that the elements contain nodes 0 1 2 of the face
+                       and not just 0 1 and 0 2...
+                       So, this time, only put an element in the list if
+                       it was in the list before.
+                    */
                     for (size_t ncnt2 = 0; ncnt2 < nhold; ncnt2++) {
-                      if (-hold_elem[ncnt2] == graph->sur_elem[side_nodes[inode]][pt_list[ncnt3]]) {
-                        hold_elem[ncnt2] = graph->sur_elem[side_nodes[inode]][pt_list[ncnt3]];
-                        break;
+                      hold_elem[ncnt2] = -hold_elem[ncnt2];
+                    }
+                    for (int ncnt3 = 0; ncnt3 < nelem; ncnt3++) {
+                      for (size_t ncnt2 = 0; ncnt2 < nhold; ncnt2++) {
+                        if (-hold_elem[ncnt2] ==
+                            graph->sur_elem[side_nodes[inode]][pt_list[ncnt3]]) {
+                          hold_elem[ncnt2] = graph->sur_elem[side_nodes[inode]][pt_list[ncnt3]];
+                          break;
+                        }
                       }
                     }
-                  }
-                  /* Now, go through list and cull out element < 0 */
-                  size_t ncnt3 = 0;
-                  for (size_t ncnt2 = 0; ncnt2 < nhold; ncnt2++) {
-                    if (hold_elem[ncnt2] >= 0) {
-                      hold_elem[ncnt3] = hold_elem[ncnt2];
-                      ncnt3++;
+                    /* Now, go through list and cull out element < 0 */
+                    size_t ncnt3 = 0;
+                    for (size_t ncnt2 = 0; ncnt2 < nhold; ncnt2++) {
+                      if (hold_elem[ncnt2] >= 0) {
+                        hold_elem[ncnt3] = hold_elem[ncnt2];
+                        ncnt3++;
+                      }
+                    }
+                    nelem = ncnt3;
+                    if (!dflag && nelem > 2) {
+                      fmt::print(
+                          stderr,
+                          "Possible corrupted mesh detected at element {}, strange connectivity.\n",
+                          ecnt);
                     }
-                  }
-                  nelem = ncnt3;
-                  if (!dflag && nelem > 2) {
-                    fmt::print(
-                        stderr,
-                        "Possible corrupted mesh detected at element {}, strange connectivity.\n",
-                        ecnt);
                   }
                 }
-              }
-              else { /* nelem == 1 or 0 */
-                if (!dflag) {
-                  nhold = graph->sur_elem[side_nodes[1]].size();
-                  for (size_t ncnt2 = 0; ncnt2 < nhold; ncnt2++) {
-                    hold_elem[ncnt2] = graph->sur_elem[side_nodes[1]][ncnt2];
+                else { /* nelem == 1 or 0 */
+                  if (!dflag) {
+                    nhold = graph->sur_elem[side_nodes[1]].size();
+                    for (size_t ncnt2 = 0; ncnt2 < nhold; ncnt2++) {
+                      hold_elem[ncnt2] = graph->sur_elem[side_nodes[1]][ncnt2];
+                    }
                   }
+                  inode = 1;
+                  node  = 3; /* The node diagonally opposite node 1 */
                 }
-                inode = 1;
-                node  = 3; /* The node diagonally opposite node 1 */
               }
             }
-          }
-        } /* "if (!hflag1)" */
-
-        /*
-         * if there is an element on this side of ecnt, then there
-         * will be at least two elements in the intersection (one
-         * will be ecnt)
-         */
-        if (nelem > 1) {
+          } /* "if (!hflag1)" */
 
           /*
-           * now go through and check each element in the list to see
-           * if it on a different processor than ecnt.  Don't need to
-           * worry about ecnt (which is in the list) since it is on
-           * the same processor as itself.  Note that due to filtering
-           * done above, we are guaranteed to either have an element
-           * on a different processor or elem==ecnt.
+           * if there is an element on this side of ecnt, then there
+           * will be at least two elements in the intersection (one
+           * will be ecnt)
            */
-          for (int ncnt = 0; ncnt < nelem; ncnt++) {
+          if (nelem > 1) {
+
+            /*
+             * now go through and check each element in the list to see
+             * if it on a different processor than ecnt.  Don't need to
+             * worry about ecnt (which is in the list) since it is on
+             * the same processor as itself.  Note that due to filtering
+             * done above, we are guaranteed to either have an element
+             * on a different processor or elem==ecnt.
+             */
+            for (int ncnt = 0; ncnt < nelem; ncnt++) {
 
-            INT elem  = hold_elem[ncnt];
-            int proc2 = lb->vertex2proc[elem];
-            assert(proc2 < machine->num_procs);
+              INT elem  = hold_elem[ncnt];
+              int proc2 = lb->vertex2proc[elem];
+              assert(proc2 < machine->num_procs);
 
-            if (proc != proc2) {
+              if (proc != proc2) {
 
-              E_Type etype2 = mesh->elem_type[elem];
+                E_Type etype2 = mesh->elem_type[elem];
 
-              int dim2 = get_elem_info(NDIM, etype2);
+                int dim2 = get_elem_info(NDIM, etype2);
 
-              int diff = abs(dim1 - dim2);
+                int diff = abs(dim1 - dim2);
 
-              /*
-               * hex's to shells - ok
-               * shells to bar - ok
-               * hex to bar - BAD since a BAR will see a HEX but a HEX will not
-               *              see a BAR
-               */
+                /*
+                 * hex's to shells - ok
+                 * shells to bar - ok
+                 * hex to bar - BAD since a BAR will see a HEX but a HEX will not
+                 *              see a BAR
+                 */
 
-              if (diff < 2) {
-
-                /* need to check for hex's */
-                hflag2 = is_hex(etype2);
-                tflag2 = is_tet(etype2);
-
-                /* check here for tet/hex combinations */
-                if ((tflag1 && hflag2) || (hflag1 && tflag2)) {
-                  /*
-                   * have to call a special function to get the side id
-                   * in these cases. In both cases, the number of side
-                   * nodes for the element will not be consistent with
-                   * side_cnt, and:
-                   *
-                   * TET/HEX - side_nodes only contains three of the
-                   *           the side nodes of the hex.
-                   *
-                   * HEX/TET - Have to check that this tet shares a side
-                   *           with the hex.
-                   */
-                  sid = get_side_id_hex_tet(mesh->elem_type[elem], mesh->connect[elem], side_cnt,
-                                            side_nodes);
-                }
-                else {
-                  /*
-                   * get the side id of elem. Make sure that ecnt is
-                   * trying to communicate to a valid side of elem
-                   */
-                  side_cnt = get_ss_mirror(etype, side_nodes, (nscnt + 1), mirror_nodes);
-
-                  /*
-                   * small kludge to handle 6 node faces butted up against
-                   * 4 node faces
-                   */
-                  if (etype == HEXSHELL && side_cnt == 6) {
-                    side_cnt = 4;
-                  }
+                if (diff < 2) {
 
-                  /*
-                   * in order to get the correct side order for elem,
-                   * get the mirror of the side of ecnt
-                   */
-                  sid = get_side_id(mesh->elem_type[elem], mesh->connect[elem], side_cnt,
-                                    mirror_nodes, problem->skip_checks, problem->partial_adj);
-                }
+                  /* need to check for hex's */
+                  hflag2 = is_hex(etype2);
+                  tflag2 = is_tet(etype2);
 
-                if (sid > 0) {
-                  /* Element is a border element */
-                  internal = false;
-                  if (!flag) {
-                    flag = 1;
-                    lb->bor_elems[proc].push_back(ecnt);
+                  /* check here for tet/hex combinations */
+                  if ((tflag1 && hflag2) || (hflag1 && tflag2)) {
+                    /*
+                     * have to call a special function to get the side id
+                     * in these cases. In both cases, the number of side
+                     * nodes for the element will not be consistent with
+                     * side_cnt, and:
+                     *
+                     * TET/HEX - side_nodes only contains three of the
+                     *           the side nodes of the hex.
+                     *
+                     * HEX/TET - Have to check that this tet shares a side
+                     *           with the hex.
+                     */
+                    sid = get_side_id_hex_tet(mesh->elem_type[elem], mesh->connect[elem], side_cnt,
+                                              side_nodes);
                   }
+                  else {
+                    /*
+                     * get the side id of elem. Make sure that ecnt is
+                     * trying to communicate to a valid side of elem
+                     */
+                    side_cnt = get_ss_mirror(etype, side_nodes, (nscnt + 1), mirror_nodes);
 
-                  /* now put ecnt into proc2's communications map */
-                  lb->e_cmap_elems[proc2].push_back(elem);
-                  lb->e_cmap_sides[proc2].push_back(sid);
-                  lb->e_cmap_procs[proc2].push_back(proc);
-                  lb->e_cmap_neigh[proc2].push_back(ecnt);
-                }
-                else if ((sid < 0) && (!problem->skip_checks)) {
-                  /*
-                   * too many errors with bad meshes, print out
-                   * more information here for diagnostics
-                   */
-                  cmesg =
-                      fmt::format("Error returned while getting side id for communication map.");
-                  Gen_Error(0, cmesg);
-                  cmesg = fmt::format("Element 1: {}", (ecnt + 1));
-                  Gen_Error(0, cmesg);
-                  nnodes = get_elem_info(NNODES, etype);
-                  cmesg  = "connect table:";
-                  for (int i = 0; i < nnodes; i++) {
-                    tmpstr = fmt::format(" {}", (size_t)(mesh->connect[ecnt][i] + 1));
-                    cmesg += tmpstr;
-                  }
-                  Gen_Error(0, cmesg);
-                  cmesg = fmt::format("side id: {}", static_cast<size_t>(nscnt + 1));
-                  Gen_Error(0, cmesg);
-                  cmesg = "side nodes:";
-                  for (int i = 0; i < side_cnt; i++) {
-                    tmpstr = fmt::format(" {}", (size_t)(side_nodes[i] + 1));
-                    cmesg += tmpstr;
+                    /*
+                     * small kludge to handle 6 node faces butted up against
+                     * 4 node faces
+                     */
+                    if (etype == HEXSHELL && side_cnt == 6) {
+                      side_cnt = 4;
+                    }
+
+                    /*
+                     * in order to get the correct side order for elem,
+                     * get the mirror of the side of ecnt
+                     */
+                    sid = get_side_id(mesh->elem_type[elem], mesh->connect[elem], side_cnt,
+                                      mirror_nodes, problem->skip_checks, problem->partial_adj);
                   }
-                  Gen_Error(0, cmesg);
-                  cmesg = fmt::format("Element 2: {}", (size_t)(elem + 1));
-                  Gen_Error(0, cmesg);
-                  nnodes = get_elem_info(NNODES, etype2);
-                  cmesg  = "connect table:";
-                  for (int i = 0; i < nnodes; i++) {
-                    tmpstr = fmt::format(" {}", (size_t)(mesh->connect[elem][i] + 1));
-                    cmesg += tmpstr;
+
+                  if (sid > 0) {
+                    /* Element is a border element */
+                    internal = false;
+                    if (!flag) {
+                      flag = 1;
+                      lb->bor_elems[proc].push_back(ecnt);
+                    }
+
+                    /* now put ecnt into proc2's communications map */
+                    lb->e_cmap_elems[proc2].push_back(elem);
+                    lb->e_cmap_sides[proc2].push_back(sid);
+                    lb->e_cmap_procs[proc2].push_back(proc);
+                    lb->e_cmap_neigh[proc2].push_back(ecnt);
                   }
-                  Gen_Error(0, cmesg);
-                  return 0; /* and get out of here */
+                  else if ((sid < 0) && (!problem->skip_checks)) {
+                    /*
+                     * too many errors with bad meshes, print out
+                     * more information here for diagnostics
+                     */
+                    cmesg =
+                        fmt::format("Error returned while getting side id for communication map.");
+                    Gen_Error(0, cmesg);
+                    cmesg = fmt::format("Element 1: {}", (ecnt + 1));
+                    Gen_Error(0, cmesg);
+                    nnodes = get_elem_info(NNODES, etype);
+                    cmesg  = "connect table:";
+                    for (int i = 0; i < nnodes; i++) {
+                      tmpstr = fmt::format(" {}", (size_t)(mesh->connect[ecnt][i] + 1));
+                      cmesg += tmpstr;
+                    }
+                    Gen_Error(0, cmesg);
+                    cmesg = fmt::format("side id: {}", static_cast<size_t>(nscnt + 1));
+                    Gen_Error(0, cmesg);
+                    cmesg = "side nodes:";
+                    for (int i = 0; i < side_cnt; i++) {
+                      tmpstr = fmt::format(" {}", (size_t)(side_nodes[i] + 1));
+                      cmesg += tmpstr;
+                    }
+                    Gen_Error(0, cmesg);
+                    cmesg = fmt::format("Element 2: {}", (size_t)(elem + 1));
+                    Gen_Error(0, cmesg);
+                    nnodes = get_elem_info(NNODES, etype2);
+                    cmesg  = "connect table:";
+                    for (int i = 0; i < nnodes; i++) {
+                      tmpstr = fmt::format(" {}", (size_t)(mesh->connect[elem][i] + 1));
+                      cmesg += tmpstr;
+                    }
+                    Gen_Error(0, cmesg);
+                    return 0; /* and get out of here */
 
-                } /* End "if sid < 0 && !problem>skip_checks" */
-              } /* End "if (sid > 0)" */
-            } /* End "if (proc != proc2)" */
-          } /* End "for (ncnt = 0; ncnt < nelem; ncnt++)" */
-        } /* End "if (nelem > 1)" */
-      } /* End "for (nscnt = 0; nscnt < nsides; nscnt++)" */
+                  } /* End "if sid < 0 && !problem>skip_checks" */
+                } /* End "if (sid > 0)" */
+              } /* End "if (proc != proc2)" */
+            } /* End "for (ncnt = 0; ncnt < nelem; ncnt++)" */
+          } /* End "if (nelem > 1)" */
+        } /* End "for (nscnt = 0; nscnt < nsides; nscnt++)" */
 
-      if (internal) {
-        lb->int_elems[proc].push_back(ecnt);
-      }
-    } /* End "for(ecnt=0; ecnt < mesh->num_elems; ecnt++)" */
+        if (internal) {
+          lb->int_elems[proc].push_back(ecnt);
+        }
+      } /* End "for(ecnt=0; ecnt < mesh->num_elems; ecnt++)" */
+    }
 
     time2 = get_time();
     fmt::print("Time for elemental categorization: {}s\n", time2 - time1);
diff --git a/packages/seacas/applications/nem_slice/elb_output.C b/packages/seacas/applications/nem_slice/elb_output.C
index 12557f5b1ff9..7e0869e38b04 100644
--- a/packages/seacas/applications/nem_slice/elb_output.C
+++ b/packages/seacas/applications/nem_slice/elb_output.C
@@ -174,10 +174,10 @@ int write_nemesis(std::string &nemI_out_file, Machine_Description *machine,
   std::string time     = fmt::format("{:%H:%M:%S}", *lt);
   std::string date     = fmt::format("{:%Y/%m/%d}", *lt);
 
-  char qa_date[15];
-  char qa_time[10];
+  char qa_date[32];
+  char qa_time[32];
   char qa_name[MAX_STR_LENGTH];
-  char qa_vers[10];
+  char qa_vers[32];
 
   copy_string(qa_time, time);
   copy_string(qa_date, date);
diff --git a/packages/seacas/applications/nem_spread/ps_pario_const.h b/packages/seacas/applications/nem_spread/ps_pario_const.h
index 43442abd6de4..916a299fbeaf 100644
--- a/packages/seacas/applications/nem_spread/ps_pario_const.h
+++ b/packages/seacas/applications/nem_spread/ps_pario_const.h
@@ -1,5 +1,5 @@
 /*
- * Copyright(C) 1999-2020, 2022, 2023 National Technology & Engineering Solutions
+ * Copyright(C) 1999-2020, 2022, 2023, 2024 National Technology & Engineering Solutions
  * of Sandia, LLC (NTESS).  Under the terms of Contract DE-NA0003525 with
  * NTESS, the U.S. Government retains certain rights in this software.
  *
@@ -8,6 +8,7 @@
 #pragma once
 
 #include "rf_io_const.h"
+#include <array>
 #include <string>
 
 /* Global variables. */
diff --git a/packages/seacas/applications/slice/SL_Version.h b/packages/seacas/applications/slice/SL_Version.h
index 1560a65a3c8e..ca02cc306020 100644
--- a/packages/seacas/applications/slice/SL_Version.h
+++ b/packages/seacas/applications/slice/SL_Version.h
@@ -9,6 +9,6 @@
 
 static const std::array<std::string, 3> qainfo{
     "slice",
-    "2024/06/10",
-    "2.3.00",
+    "2024/07/17",
+    "2.3.01",
 };
diff --git a/packages/seacas/applications/slice/Slice.C b/packages/seacas/applications/slice/Slice.C
index be73865ceb9e..2bba93b462ed 100644
--- a/packages/seacas/applications/slice/Slice.C
+++ b/packages/seacas/applications/slice/Slice.C
@@ -912,6 +912,8 @@ namespace {
                           size_t proc_size)
   {
     progress(__func__);
+    size_t spatial_dimension = region.get_property("spatial_dimension").get_int();
+
     std::vector<double> glob_coord_x;
     std::vector<double> glob_coord_y;
     std::vector<double> glob_coord_z;
@@ -968,8 +970,12 @@ namespace {
     }
     else {
       gnb->get_field_data("mesh_model_coordinates_x", glob_coord_x);
-      gnb->get_field_data("mesh_model_coordinates_y", glob_coord_y);
-      gnb->get_field_data("mesh_model_coordinates_z", glob_coord_z);
+      if (spatial_dimension > 1) {
+        gnb->get_field_data("mesh_model_coordinates_y", glob_coord_y);
+      }
+      if (spatial_dimension > 2) {
+        gnb->get_field_data("mesh_model_coordinates_z", glob_coord_z);
+      }
       progress("\tRead global mesh_model_coordinates");
 
       for (size_t i = 0; i < node_count; i++) {
@@ -993,8 +999,12 @@ namespace {
     for (size_t p = proc_begin; p < proc_begin + proc_size; p++) {
       Ioss::NodeBlock *nb = proc_region[p]->get_node_blocks()[0];
       nb->put_field_data("mesh_model_coordinates_x", coordinates_x[p]);
-      nb->put_field_data("mesh_model_coordinates_y", coordinates_y[p]);
-      nb->put_field_data("mesh_model_coordinates_z", coordinates_z[p]);
+      if (spatial_dimension > 1) {
+        nb->put_field_data("mesh_model_coordinates_y", coordinates_y[p]);
+      }
+      if (spatial_dimension > 2) {
+        nb->put_field_data("mesh_model_coordinates_z", coordinates_z[p]);
+      }
       proc_progress(p, processor_count);
     }
     progress("\tOutput processor coordinate vectors");
@@ -1028,7 +1038,9 @@ namespace {
     }
     progress("\tReserve processor coordinate vectors");
 
-    for (size_t comp = 0; comp < 3; comp++) {
+    size_t spatial_dimension = region.get_property("spatial_dimension").get_int();
+
+    for (size_t comp = 0; comp < spatial_dimension; comp++) {
       for (size_t p = proc_begin; p < proc_begin + proc_size; p++) {
         coordinates[p].resize(0);
       }
@@ -1292,9 +1304,10 @@ namespace {
         offset += element_count;
       }
     }
+    size_t spatial_dimension = region.get_property("spatial_dimension").get_int();
     for (size_t p = 0; p < proc_count; p++) {
-      auto *nb =
-          new Ioss::NodeBlock(proc_region[p]->get_database(), "node_block1", on_proc_count[p], 3);
+      auto *nb = new Ioss::NodeBlock(proc_region[p]->get_database(), "node_block1",
+                                     on_proc_count[p], spatial_dimension);
       proc_region[p]->add(nb);
       if (debug_level & 2) {
         fmt::print(stderr, "\tProcessor {} has {} nodes.\n", fmt::group_digits(p),
diff --git a/packages/seacas/applications/zellij/Cell.C b/packages/seacas/applications/zellij/Cell.C
index 30d13d8014ac..53b0d9f34710 100644
--- a/packages/seacas/applications/zellij/Cell.C
+++ b/packages/seacas/applications/zellij/Cell.C
@@ -1,4 +1,4 @@
-// Copyright(C) 2021, 2022, 2023 National Technology & Engineering Solutions
+// Copyright(C) 2021, 2022, 2023, 2024 National Technology & Engineering Solutions
 // of Sandia, LLC (NTESS).  Under the terms of Contract DE-NA0003525 with
 // NTESS, the U.S. Government retains certain rights in this software.
 //
@@ -21,7 +21,7 @@ extern unsigned int debug_level;
 template <> struct fmt::formatter<Loc> : formatter<std::string>
 {
   // parse is inherited from formatter<std::string>.
-  template <typename FormatContext> auto format(Loc l, FormatContext &ctx)
+  template <typename FormatContext> auto format(Loc l, FormatContext &ctx) const
   {
     std::string name = "unknown";
     switch (l) {
diff --git a/packages/seacas/applications/zellij/Cell.h b/packages/seacas/applications/zellij/Cell.h
index 8db0dac91646..5006063f04d3 100644
--- a/packages/seacas/applications/zellij/Cell.h
+++ b/packages/seacas/applications/zellij/Cell.h
@@ -150,7 +150,7 @@ class Cell
   double m_offY{0.0};
 
 private:
-  //! The UnitCell that occupies this location in the grid / latice
+  //! The UnitCell that occupies this location in the grid / lattice
   std::shared_ptr<UnitCell> m_unitCell;
 
   //! The MPI ranks of all surrounding cells in order:
diff --git a/packages/seacas/applications/zellij/UnitCell.C b/packages/seacas/applications/zellij/UnitCell.C
index ccd98e996a7d..5ecc781ba198 100644
--- a/packages/seacas/applications/zellij/UnitCell.C
+++ b/packages/seacas/applications/zellij/UnitCell.C
@@ -279,7 +279,7 @@ void UnitCell::generate_boundary_faces(unsigned int which_faces)
   auto                   &faces = face_generator.faces("ALL");
   Ioss::ElementBlock     *block = nullptr;
   for (const auto &face : faces) {
-    if (face.elementCount_ == 1) {
+    if (face.element_count() == 1) {
       block             = get_element_block(block, face.element[0] / 10, m_region);
       auto block_offset = block->get_offset();
       for (int i = 0; i < 6; i++) {
diff --git a/packages/seacas/cmake/tpls/FindTPLADIOS2.cmake b/packages/seacas/cmake/tpls/FindTPLADIOS2.cmake
deleted file mode 100644
index bddbe96e9ca4..000000000000
--- a/packages/seacas/cmake/tpls/FindTPLADIOS2.cmake
+++ /dev/null
@@ -1,90 +0,0 @@
-# @HEADER
-# ************************************************************************
-#
-#            Trilinos: An Object-Oriented Solver Framework
-#                 Copyright (2001) Sandia Corporation
-#
-#
-# Copyright (2001) Sandia Corporation. Under the terms of Contract
-# DE-AC04-94AL85000, there is a non-exclusive license for use of this
-# work by or on behalf of the U.S. Government.  Export of this program
-# may require a license from the United States Government.
-#
-# 1. Redistributions of source code must retain the above copyright
-# notice, this list of conditions and the following disclaimer.
-#
-# 2. Redistributions in binary form must reproduce the above copyright
-# notice, this list of conditions and the following disclaimer in the
-# documentation and/or other materials provided with the distribution.
-#
-# 3. Neither the name of the Corporation nor the names of the
-# contributors may be used to endorse or promote products derived from
-# this software without specific prior written permission.
-#
-# THIS SOFTWARE IS PROVIDED BY SANDIA CORPORATION "AS IS" AND ANY
-# EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
-# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
-# PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL SANDIA CORPORATION OR THE
-# CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
-# EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
-# PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
-# PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
-# LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
-# NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
-# SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-#
-# NOTICE:  The United States Government is granted for itself and others
-# acting on its behalf a paid-up, nonexclusive, irrevocable worldwide
-# license in this data to reproduce, prepare derivative works, and
-# perform publicly and display publicly.  Beginning five (5) years from
-# July 25, 2001, the United States Government is granted for itself and
-# others acting on its behalf a paid-up, nonexclusive, irrevocable
-# worldwide license in this data to reproduce, prepare derivative works,
-# distribute copies to the public, perform publicly and display
-# publicly, and to permit others to do so.
-#
-# NEITHER THE UNITED STATES GOVERNMENT, NOR THE UNITED STATES DEPARTMENT
-# OF ENERGY, NOR SANDIA CORPORATION, NOR ANY OF THEIR EMPLOYEES, MAKES
-# ANY WARRANTY, EXPRESS OR IMPLIED, OR ASSUMES ANY LEGAL LIABILITY OR
-# RESPONSIBILITY FOR THE ACCURACY, COMPLETENESS, OR USEFULNESS OF ANY
-# INFORMATION, APPARATUS, PRODUCT, OR PROCESS DISCLOSED, OR REPRESENTS
-# THAT ITS USE WOULD NOT INFRINGE PRIVATELY OWNED RIGHTS.
-#
-# ************************************************************************
-# @HEADER
-
-
-MESSAGE("-- Using FIND_PACKAGE(ADIOS2 ...) ...")
-
-FIND_PACKAGE(ADIOS2)
-
-IF (ADIOS2_FOUND)
-    # Tell TriBITS that we found ADIOS2 and there no need to look any further!
-    GET_TARGET_PROPERTY(_ADIOS2_INCLUDE_DIRS adios2::adios2 INTERFACE_INCLUDE_DIRECTORIES)
-    GET_TARGET_PROPERTY(_ADIOS2_LIBRARY_LOCATION adios2::adios2 LOCATION)
-    GET_FILENAME_COMPONENT(ADIOS2_LIBRARY_DIRS ${_ADIOS2_LIBRARY_LOCATION} DIRECTORY)
-
-# For compatibility with TriBITS:
-SET(DOCSTR "List of semi-colon separated paths to look for the TPL ADIOS2")
-
-GET_TARGET_PROPERTY(ADIOS2_LOCATION adios2::adios2 LOCATION)
-
-SET(TPL_ADIOS2_LIBRARIES ${ADIOS2_LOCATION} CACHE PATH ${DOCSTR})
-SET(TPL_ADIOS2_INCLUDE_DIRS ${_ADIOS2_INCLUDE_DIRS} CACHE PATH ${DOCSTR})
-SET(TPL_ADIOS2_LIBRARY_DIRS ${_ADIOS2_LIBRARY_DIRS} CACHE PATH ${DOCSTR})
-
-ENDIF()
-
-#
-# Third, call TRIBITS_TPL_FIND_INCLUDE_DIRS_AND_LIBRARIES()
-#
-TRIBITS_TPL_FIND_INCLUDE_DIRS_AND_LIBRARIES( ADIOS2
-  REQUIRED_HEADERS adios2.h
-  REQUIRED_LIBS_NAMES adios2_cxx11_mpi,adios2_cxx11,adios2_core_mpi,adios2_core
-  )
-
-# NOTE: If FIND_PACKAGE(ADIOS2 ...) was called and successfully found ADIOS2, then
-# TRIBITS_TPL_FIND_INCLUDE_DIRS_AND_LIBRARIES() will use the already-set
-# variables TPL_ADIOS2_INCLUDE_DIRS and TPL_ADIOS2_LIBRARIES and then print them
-# out (and set some other standard variables as well).  This is the final
-# "hook" into the TriBITS TPL system.
diff --git a/packages/seacas/libraries/aprepro_lib/CMakeLists.txt b/packages/seacas/libraries/aprepro_lib/CMakeLists.txt
index b1665f2b28b5..13fcf791dda3 100644
--- a/packages/seacas/libraries/aprepro_lib/CMakeLists.txt
+++ b/packages/seacas/libraries/aprepro_lib/CMakeLists.txt
@@ -15,8 +15,6 @@ IF (${CMAKE_PROJECT_NAME}_ENABLE_SEACASExodus)
   ADD_DEFINITIONS(-DEXODUS_SUPPORT)
 ENDIF()
 
-ADD_DEFINITIONS(-DFMT_SUPPORT)
-
 TRIBITS_INCLUDE_DIRECTORIES(
   ${CMAKE_CURRENT_SOURCE_DIR}
 )
diff --git a/packages/seacas/libraries/exodus/include/exodusII.h b/packages/seacas/libraries/exodus/include/exodusII.h
index dd545b5ec7c1..8c978d67aa2a 100644
--- a/packages/seacas/libraries/exodus/include/exodusII.h
+++ b/packages/seacas/libraries/exodus/include/exodusII.h
@@ -55,12 +55,12 @@
 #endif
 
 /* EXODUS version number */
-#define EXODUS_VERSION       "9.00"
+#define EXODUS_VERSION       "9.01"
 #define EXODUS_VERSION_MAJOR 9
-#define EXODUS_VERSION_MINOR 0
-#define EXODUS_RELEASE_DATE  "May 30, 2024"
+#define EXODUS_VERSION_MINOR 1
+#define EXODUS_RELEASE_DATE  "July 17, 2024"
 
-#define EX_API_VERS       9.00f
+#define EX_API_VERS       9.01f
 #define EX_API_VERS_NODOT (100 * EXODUS_VERSION_MAJOR + EXODUS_VERSION_MINOR)
 #define EX_VERS           EX_API_VERS
 
@@ -1045,6 +1045,8 @@ EXODUS_EXPORT int ex_get_blob(int exoid, struct ex_blob *blob);
 EXODUS_EXPORT int ex_put_blobs(int exoid, size_t count, const struct ex_blob *blobs);
 EXODUS_EXPORT int ex_get_blobs(int exoid, struct ex_blob *blobs);
 
+EXODUS_EXPORT int ex_put_multi_field_metadata(int exoid, const ex_field *field,
+                                              const int field_count);
 EXODUS_EXPORT int ex_put_field_metadata(int exoid, const ex_field field);
 EXODUS_EXPORT int ex_put_field_suffices(int exoid, const ex_field field, const char *suffices);
 EXODUS_EXPORT int ex_get_field_metadata(int exoid, ex_field *field);
@@ -1953,6 +1955,7 @@ enum ex_error_return_code {
   EX_LASTERR       = -1003, /**< in ex_err, use existing err_num value */
   EX_NULLENTITY    = -1006, /**< null entity found                        */
   EX_NOENTITY      = -1007, /**< no entities of that type on database    */
+  EX_INTSIZEMISMATCH = -1008, /**< integer sizes do not match on input/output databases in ex_copy  */
   EX_NOTFOUND      = -1008, /**< could not find requested variable on database */
 
   EX_FATAL = -1, /**< fatal error flag def                     */
diff --git a/packages/seacas/libraries/exodus/include/exodusII_cfg.h.in b/packages/seacas/libraries/exodus/include/exodusII_cfg.h.in
index f407c0ed7964..304c65b4c734 100644
--- a/packages/seacas/libraries/exodus/include/exodusII_cfg.h.in
+++ b/packages/seacas/libraries/exodus/include/exodusII_cfg.h.in
@@ -1,8 +1,10 @@
-# Copyright(C) 1999-2022 National Technology & Engineering Solutions
-# of Sandia, LLC (NTESS).  Under the terms of Contract DE-NA0003525 with
-# NTESS, the U.S. Government retains certain rights in this software.
-#
-# See packages/seacas/LICENSE for details
+/*
+ * Copyright(C) 1999-2022 National Technology & Engineering Solutions
+ * of Sandia, LLC (NTESS).  Under the terms of Contract DE-NA0003525 with
+ * NTESS, the U.S. Government retains certain rights in this software.
+ *
+ * See packages/seacas/LICENSE for details
+ */
 #pragma once
 
 #cmakedefine EXODUSII_BUILD_SHARED_LIBS
diff --git a/packages/seacas/libraries/exodus/include/exodusII_int.h b/packages/seacas/libraries/exodus/include/exodusII_int.h
index 8657fa6755dc..e8bb5aca4ebc 100644
--- a/packages/seacas/libraries/exodus/include/exodusII_int.h
+++ b/packages/seacas/libraries/exodus/include/exodusII_int.h
@@ -91,7 +91,7 @@ extern "C" {
 /* Utility function to find variable to store entity attribute on */
 int exi_get_varid(int exoid, ex_entity_type obj_type, ex_entity_id id);
 
-void exi_reset_error_status(void);
+EXODUS_EXPORT void exi_reset_error_status(void);
 
 #if defined(EXODUS_THREADSAFE)
 #if !defined(exerrval)
@@ -686,28 +686,31 @@ typedef enum exi_element_type exi_element_type;
 struct exi_file_item
 {
   int          file_id;
-  nc_type      netcdf_type_code;
+  nc_type      netcdf_type_code; /**< NC_FLOAT or NC_DOUBLE */
   int          int64_status;
   int          maximum_name_length;
   int          time_varid; /* Store to avoid lookup each timestep */
   unsigned int assembly_count;
   unsigned int blob_count;
+  unsigned int compression_level;        /**< 0 (disabled) to 9 (maximum) compression level for
+                                            gzip, 4..32 and even for szip; NetCDF-4 only */
+  unsigned int persist_define_mode : 10; /**< Stay in define mode until exi_persist_leavedef is
+                                            called. Set by exi_persist_redef... */
   unsigned int
-      compression_algorithm : 2;      /**< GZIP/ZLIB, SZIP, more may be supported by NetCDF soon */
-  unsigned int compression_level : 6; /**< 0 (disabled) to 9 (maximum) compression level for
-                                         gzip, 4..32 and even for szip; NetCDF-4 only */
+      compression_algorithm : 4; /**< GZIP/ZLIB, SZIP, more may be supported by NetCDF soon */
+  unsigned int shuffle : 1;      /**< 1 true, 0 false */
   unsigned int user_compute_wordsize : 1; /**< 0 for 4 byte or 1 for 8 byte reals */
-  unsigned int shuffle : 1;               /**< 1 true, 0 false */
   unsigned int
       file_type : 2; /**< 0 - classic, 1 -- 64 bit classic, 2 --NetCDF4,  3 --NetCDF4 classic */
-  unsigned int          is_write : 1;    /**< for output or append */
-  unsigned int          is_parallel : 1; /**< 1 true, 0 false */
-  unsigned int          is_hdf5 : 1;     /**< 1 true, 0 false */
-  unsigned int          is_pnetcdf : 1;  /**< 1 true, 0 false */
-  unsigned int          has_nodes : 1;   /**< for input only at this time */
-  unsigned int          has_edges : 1;   /**< for input only at this time */
-  unsigned int          has_faces : 1;   /**< for input only at this time */
-  unsigned int          has_elems : 1;   /**< for input only at this time */
+  unsigned int          is_write : 1;       /**< for output or append */
+  unsigned int          is_parallel : 1;    /**< 1 true, 0 false */
+  unsigned int          is_hdf5 : 1;        /**< 1 true, 0 false */
+  unsigned int          is_pnetcdf : 1;     /**< 1 true, 0 false */
+  unsigned int          has_nodes : 1;      /**< for input only at this time */
+  unsigned int          has_edges : 1;      /**< for input only at this time */
+  unsigned int          has_faces : 1;      /**< for input only at this time */
+  unsigned int          has_elems : 1;      /**< for input only at this time */
+  unsigned int          in_define_mode : 1; /**< Is the file in nc define mode... */
   struct exi_file_item *next;
 };
 
@@ -796,9 +799,9 @@ extern struct exi_obj_stats *exoII_edm;
 extern struct exi_obj_stats *exoII_fam;
 extern struct exi_obj_stats *exoII_nm;
 
-struct exi_file_item *exi_find_file_item(int exoid);
-struct exi_file_item *exi_add_file_item(int exoid);
-struct exi_obj_stats *exi_get_stat_ptr(int exoid, struct exi_obj_stats **obj_ptr);
+EXODUS_EXPORT struct exi_file_item *exi_find_file_item(int exoid);
+struct exi_file_item               *exi_add_file_item(int exoid);
+struct exi_obj_stats               *exi_get_stat_ptr(int exoid, struct exi_obj_stats **obj_ptr);
 
 EXODUS_EXPORT void exi_rm_stat_ptr(int exoid, struct exi_obj_stats **obj_ptr);
 
@@ -854,9 +857,14 @@ EXODUS_EXPORT int  exi_put_names(int exoid, int varid, size_t num_entity, char *
                                  ex_entity_type obj_type, const char *subtype, const char *routine);
 EXODUS_EXPORT void exi_trim(char *name);
 EXODUS_EXPORT void exi_update_max_name_length(int exoid, int length);
+EXODUS_EXPORT int  exi_redef(int exoid, const char *call_func);
+EXODUS_EXPORT int  exi_persist_redef(int exoid, const char *call_func);
 EXODUS_EXPORT int  exi_leavedef(int         exoid,    /* NemesisI file ID         */
                                 const char *call_rout /* Name of calling function */
  );
+EXODUS_EXPORT int  exi_persist_leavedef(int         exoid,    /* NemesisI file ID         */
+                                        const char *call_rout /* Name of calling function */
+ );
 
 EXODUS_EXPORT int exi_check_version(int run_version);
 EXODUS_EXPORT int exi_handle_mode(unsigned int my_mode, int is_parallel, int run_version);
diff --git a/packages/seacas/libraries/exodus/src/ex__put_homogenous_block_params.c b/packages/seacas/libraries/exodus/src/ex__put_homogenous_block_params.c
index ed4e31d7200b..0e16d4a9e0f8 100644
--- a/packages/seacas/libraries/exodus/src/ex__put_homogenous_block_params.c
+++ b/packages/seacas/libraries/exodus/src/ex__put_homogenous_block_params.c
@@ -118,7 +118,7 @@ int exi_put_homogenous_block_params(int exoid, size_t block_count, const struct
 
   /* ======================================================================== */
   /* put netcdf file into define mode  */
-  if ((status = nc_redef(exoid)) != NC_NOERR) {
+  if ((status = exi_redef(exoid, __func__)) != NC_NOERR) {
     snprintf(errmsg, MAX_ERR_LENGTH, "ERROR: failed to place file id %d into define mode", exoid);
     ex_err_fn(exoid, __func__, errmsg, status);
     return (EX_FATAL);
diff --git a/packages/seacas/libraries/exodus/src/ex_add_attr.c b/packages/seacas/libraries/exodus/src/ex_add_attr.c
index 5d10849df2ce..a0f0e94776d3 100644
--- a/packages/seacas/libraries/exodus/src/ex_add_attr.c
+++ b/packages/seacas/libraries/exodus/src/ex_add_attr.c
@@ -123,7 +123,7 @@ int ex_add_attr(int exoid, ex_entity_type obj_type, ex_entity_id obj_id, int64_t
 
   /* element attribute array */
   /* put netcdf file into define mode  */
-  if ((status = nc_redef(exoid)) != NC_NOERR) {
+  if ((status = exi_redef(exoid, __func__)) != NC_NOERR) {
     snprintf(errmsg, MAX_ERR_LENGTH, "ERROR: failed to place file id %d into define mode", exoid);
     ex_err_fn(exoid, __func__, errmsg, status);
     EX_FUNC_LEAVE(EX_FATAL);
diff --git a/packages/seacas/libraries/exodus/src/ex_close.c b/packages/seacas/libraries/exodus/src/ex_close.c
index 171f9559c901..33ac81497e08 100644
--- a/packages/seacas/libraries/exodus/src/ex_close.c
+++ b/packages/seacas/libraries/exodus/src/ex_close.c
@@ -1,5 +1,5 @@
 /*
- * Copyright(C) 1999-2020, 2022, 2023 National Technology & Engineering Solutions
+ * Copyright(C) 1999-2020, 2022, 2023, 2024 National Technology & Engineering Solutions
  * of Sandia, LLC (NTESS).  Under the terms of Contract DE-NA0003525 with
  * NTESS, the U.S. Government retains certain rights in this software.
  *
@@ -57,6 +57,11 @@ int ex_close(int exoid)
     EX_FUNC_LEAVE(EX_FATAL);
   }
 
+#ifndef NDEBUG
+  struct exi_file_item *file = exi_find_file_item(exoid);
+  assert(!file->in_define_mode && file->persist_define_mode == 0);
+#endif
+
   /*
    * NOTE: If using netcdf-4, exoid must refer to the root group.
    * Need to determine whether there are any groups and if so,
diff --git a/packages/seacas/libraries/exodus/src/ex_conv.c b/packages/seacas/libraries/exodus/src/ex_conv.c
index bbb545e9c3ed..f053f185d37c 100644
--- a/packages/seacas/libraries/exodus/src/ex_conv.c
+++ b/packages/seacas/libraries/exodus/src/ex_conv.c
@@ -249,6 +249,8 @@ int exi_conv_init(int exoid, int *comp_wordsize, int *io_wordsize, int file_word
   new_file->has_edges             = 1;
   new_file->has_faces             = 1;
   new_file->has_elems             = 1;
+  new_file->in_define_mode        = 0;
+  new_file->persist_define_mode   = 0;
   new_file->is_write              = is_write;
 
   new_file->next = file_list;
diff --git a/packages/seacas/libraries/exodus/src/ex_copy.c b/packages/seacas/libraries/exodus/src/ex_copy.c
index e7807dc9d4ac..8ccb00505f2b 100644
--- a/packages/seacas/libraries/exodus/src/ex_copy.c
+++ b/packages/seacas/libraries/exodus/src/ex_copy.c
@@ -1,5 +1,5 @@
 /*
- * Copyright(C) 1999-2023 National Technology & Engineering Solutions
+ * Copyright(C) 1999-2024 National Technology & Engineering Solutions
  * of Sandia, LLC (NTESS).  Under the terms of Contract DE-NA0003525 with
  * NTESS, the U.S. Government retains certain rights in this software.
  *
@@ -108,7 +108,7 @@ static int ex_copy_internal(int in_exoid, int out_exoid, int mesh_only)
   }
 
   /* put output file into define mode */
-  EXCHECK(nc_redef(out_exoid));
+  EXCHECK(exi_redef(out_exoid, __func__));
 
   /* copy global attributes */
   EXCHECK(cpy_global_att(in_exoid, out_exoid));
diff --git a/packages/seacas/libraries/exodus/src/ex_create_group.c b/packages/seacas/libraries/exodus/src/ex_create_group.c
index 3d05f0ce541f..0adc0c3595b4 100644
--- a/packages/seacas/libraries/exodus/src/ex_create_group.c
+++ b/packages/seacas/libraries/exodus/src/ex_create_group.c
@@ -1,5 +1,5 @@
 /*
- * Copyright(C) 1999-2020, 2022 National Technology & Engineering Solutions
+ * Copyright(C) 1999-2020, 2022, 2024 National Technology & Engineering Solutions
  * of Sandia, LLC (NTESS).  Under the terms of Contract DE-NA0003525 with
  * NTESS, the U.S. Government retains certain rights in this software.
  *
@@ -26,7 +26,7 @@ int ex_create_group(int parent_id, const char *group_name)
     EX_FUNC_LEAVE(EX_FATAL);
   }
 
-  if ((status = nc_redef(parent_id)) != NC_NOERR) {
+  if ((status = exi_redef(parent_id, __func__)) != NC_NOERR) {
     snprintf(errmsg, MAX_ERR_LENGTH, "ERROR: failed to put file id %d into define mode", parent_id);
     ex_err_fn(exoid, __func__, errmsg, status);
     EX_FUNC_LEAVE(EX_FATAL);
diff --git a/packages/seacas/libraries/exodus/src/ex_err.c b/packages/seacas/libraries/exodus/src/ex_err.c
index e3d95e4f0113..a2400ab978c9 100644
--- a/packages/seacas/libraries/exodus/src/ex_err.c
+++ b/packages/seacas/libraries/exodus/src/ex_err.c
@@ -333,7 +333,8 @@ const char *ex_strerror(int err_num)
   case EX_MEMFAIL: return "Memory allocation failure";
   case EX_BADFILEMODE: return "Bad file mode -- cannot specify both EX_READ and EX_WRITE";
   case EX_BADFILEID: return "Bad file id. Could not find exodus file associated with file id.";
-  case EX_WRONGFILETYPE: return "Integer sizes must match for input and output file in ex_copy.";
+  case EX_WRONGFILETYPE:
+    return "File does not exist or is not of a supported type (netcdf3, netcdf4, netcdf5).";
   case EX_LOOKUPFAIL:
     return "Id lookup failed for specified entity type. Could not find entity with specified id.";
   case EX_BADFILENAME: return "Empty or null filename specified.";
@@ -344,6 +345,7 @@ const char *ex_strerror(int err_num)
   case EX_INTERNAL: return "Internal logic error in exodus library.";
   case EX_NOTROOTID: return "File id is not the root id; it is a subgroup id.";
   case EX_NULLENTITY: return "Null entity found.";
+  case EX_INTSIZEMISMATCH: return "Integer sizes must match for input and output file in ex_copy.";
   case EX_MSG: return "Message printed; no error implied.";
   default: return nc_strerror(err_num);
   }
diff --git a/packages/seacas/libraries/exodus/src/ex_field_utils.c b/packages/seacas/libraries/exodus/src/ex_field_utils.c
index df99363788d5..098e3c589f26 100644
--- a/packages/seacas/libraries/exodus/src/ex_field_utils.c
+++ b/packages/seacas/libraries/exodus/src/ex_field_utils.c
@@ -9,7 +9,6 @@
 #include "exodusII.h"     // for ex_err, etc
 #include "exodusII_int.h" // for EX_FATAL, etc
 #include <assert.h>
-#include <math.h>
 #define _GNU_SOURCE
 #include <string.h>
 
@@ -43,13 +42,19 @@ static size_t my_strlcat(char *restrict dst, const char *restrict src, size_t ma
   return dstlen + srclen;
 }
 
-static int number_width(const size_t number)
+static int number_width(size_t number)
 {
+  /* Could use `(int)floor(log10(number)) + 1`, but that requires math library... */
   if (number == 0) {
     return 1;
   }
-  int width = (int)floor(log10(number)) + 1;
-  return width;
+  int count = 0;
+  // Iterate till n has digits remaining
+  while (number != 0) {
+    number /= 10;
+    ++count;
+  }
+  return count;
 }
 
 static void verify_valid_component(int component, size_t cardinality, size_t suffix_size)
diff --git a/packages/seacas/libraries/exodus/src/ex_get_field_metadata.c b/packages/seacas/libraries/exodus/src/ex_get_field_metadata.c
index 7d1dbdd70e7f..1d25ed3c2956 100644
--- a/packages/seacas/libraries/exodus/src/ex_get_field_metadata.c
+++ b/packages/seacas/libraries/exodus/src/ex_get_field_metadata.c
@@ -122,11 +122,11 @@ int ex_get_field_metadata(int exoid, ex_field *field)
   EX_FUNC_ENTER();
 
   int varid;
-  int att_count = exi_get_attribute_count(exoid, field->entity_type, field->entity_id, &varid);
+  int att_count = exi_get_attribute_count(exoid, field[0].entity_type, field[0].entity_id, &varid);
   if (att_count < 0) {
     char errmsg[MAX_ERR_LENGTH];
     snprintf(errmsg, MAX_ERR_LENGTH, "ERROR: Negative attribute count (%d) on %s with id %" PRId64,
-             att_count, ex_name_of_object(field->entity_type), field->entity_id);
+             att_count, ex_name_of_object(field[0].entity_type), field[0].entity_id);
     ex_err_fn(exoid, __func__, errmsg, EX_INTERNAL);
     EX_FUNC_LEAVE(EX_FATAL);
   }
@@ -140,7 +140,7 @@ int ex_get_field_metadata(int exoid, ex_field *field)
       char errmsg[MAX_ERR_LENGTH];
       snprintf(errmsg, MAX_ERR_LENGTH,
                "ERROR: failed to get attribute named %s on %s with id %" PRId64, attr_name,
-               ex_name_of_object(field->entity_type), field->entity_id);
+               ex_name_of_object(field[0].entity_type), field[0].entity_id);
       ex_err_fn(exoid, __func__, errmsg, status);
       EX_FUNC_LEAVE(EX_FATAL);
     }
@@ -165,6 +165,10 @@ int ex_get_field_metadata(int exoid, ex_field *field)
       if (found == -1) {
         which = count;
         strcpy(field[count].name, fld_name);
+	/* Set default separator type... */
+	field[count].component_separator[0] = '_';
+	field[count].component_separator[1] = '\0';
+
         count++;
       }
 
@@ -174,7 +178,7 @@ int ex_get_field_metadata(int exoid, ex_field *field)
         char errmsg[MAX_ERR_LENGTH];
         snprintf(errmsg, MAX_ERR_LENGTH,
                  "ERROR: failed to get parameters for attribute named %s on %s with id %" PRId64,
-                 attr_name, ex_name_of_object(field->entity_type), field->entity_id);
+                 attr_name, ex_name_of_object(field[0].entity_type), field[0].entity_id);
         ex_err_fn(exoid, __func__, errmsg, status);
         EX_FUNC_LEAVE(EX_FATAL);
       }
@@ -205,7 +209,7 @@ int ex_get_field_metadata(int exoid, ex_field *field)
         snprintf(
             errmsg, MAX_ERR_LENGTH,
             "ERROR: Invalid field metadata attribute type %s on field %s on %s with id %" PRId64,
-            fld_type, fld_name, ex_name_of_object(field->entity_type), field->entity_id);
+            fld_type, fld_name, ex_name_of_object(field[0].entity_type), field[0].entity_id);
         ex_err_fn(exoid, __func__, errmsg, status);
         EX_FUNC_LEAVE(EX_FATAL);
       }
@@ -214,7 +218,7 @@ int ex_get_field_metadata(int exoid, ex_field *field)
         snprintf(errmsg, MAX_ERR_LENGTH,
                  "ERROR: failed to read field metadata attribute type %s on field %s on %s with id "
                  "%" PRId64,
-                 fld_type, fld_name, ex_name_of_object(field->entity_type), field->entity_id);
+                 fld_type, fld_name, ex_name_of_object(field[0].entity_type), field[0].entity_id);
         ex_err_fn(exoid, __func__, errmsg, status);
         EX_FUNC_LEAVE(EX_FATAL);
       }
diff --git a/packages/seacas/libraries/exodus/src/ex_get_group_id.c b/packages/seacas/libraries/exodus/src/ex_get_group_id.c
index d98c8ca401d6..c07ac1f1b7c4 100644
--- a/packages/seacas/libraries/exodus/src/ex_get_group_id.c
+++ b/packages/seacas/libraries/exodus/src/ex_get_group_id.c
@@ -1,5 +1,5 @@
 /*
- * Copyright(C) 1999-2020 National Technology & Engineering Solutions
+ * Copyright(C) 1999-2020, 2024, 2024 National Technology & Engineering Solutions
  * of Sandia, LLC (NTESS).  Under the terms of Contract DE-NA0003525 with
  * NTESS, the U.S. Government retains certain rights in this software.
  *
@@ -23,12 +23,15 @@ int ex_get_group_id(int parent_id, const char *group_name, int *group_id)
   char errmsg[MAX_ERR_LENGTH];
 #if NC_HAS_HDF5
   EX_FUNC_ENTER();
-  /* See if name contains "/" indicating it is a full path name... */
-  if (group_name == NULL) {
+  /* If the `group_name` is NULL, or is the single character '/', then
+   * return the root id.
+   */
+  if (group_name == NULL || (group_name[0] == '/' && group_name[1] == '\0')) {
     /* Return root */
     *group_id = (unsigned)parent_id & EX_FILE_ID_MASK;
   }
-  else if (strchr(group_name, '/') == NULL) {
+  /* If the name does not start with "/" then it is a relative name from current location... */
+  else if (group_name[0] != '/') {
     /* Local child */
     int status = nc_inq_grp_ncid(parent_id, group_name, group_id);
     if (status != NC_NOERR) {
diff --git a/packages/seacas/libraries/exodus/src/ex_open.c b/packages/seacas/libraries/exodus/src/ex_open.c
index f8014692d4ba..baac050f4a14 100644
--- a/packages/seacas/libraries/exodus/src/ex_open.c
+++ b/packages/seacas/libraries/exodus/src/ex_open.c
@@ -1,5 +1,5 @@
 /*
- * Copyright(C) 1999-2023 National Technology & Engineering Solutions
+ * Copyright(C) 1999-2024 National Technology & Engineering Solutions
  * of Sandia, LLC (NTESS).  Under the terms of Contract DE-NA0003525 with
  * NTESS, the U.S. Government retains certain rights in this software.
  *
@@ -253,8 +253,8 @@ int ex_open_int(const char *path, int mode, int *comp_ws, int *io_ws, float *ver
         EX_FUNC_LEAVE(EX_FATAL);
       }
       snprintf(errmsg, MAX_ERR_LENGTH,
-               "ERROR: failed to open %s of type %d for reading.\n\tEither "
-               "the file does not exist,\n\tor there is a permission or file "
+               "ERROR: failed to open %s of type %d for reading.\n\t\tThe "
+               "file does not exist, or there is a permission or file "
                "format issue.",
                canon_path, type);
       ex_err(__func__, errmsg, status);
@@ -298,6 +298,7 @@ int ex_open_int(const char *path, int mode, int *comp_ws, int *io_ws, float *ver
     int    dim_str_name = 0;
     int    stat_dim     = nc_inq_dimid(exoid, DIM_STR_NAME, &dim_str_name);
     if (stat_att != NC_NOERR || stat_dim != NC_NOERR) {
+      /* This must still be nc_redef */
       if ((status = nc_redef(exoid)) != NC_NOERR) {
         snprintf(errmsg, MAX_ERR_LENGTH,
                  "ERROR: failed to place file id %d named %s into define mode", exoid, canon_path);
@@ -332,7 +333,7 @@ int ex_open_int(const char *path, int mode, int *comp_ws, int *io_ws, float *ver
           EX_FUNC_LEAVE(EX_FATAL);
         }
       }
-      if ((status = exi_leavedef(exoid, __func__)) != NC_NOERR) {
+      if ((status = nc_enddef(exoid)) != NC_NOERR) {
         snprintf(errmsg, MAX_ERR_LENGTH, "ERROR: failed to exit define mode in file id %d", exoid);
         ex_err_fn(exoid, __func__, errmsg, status);
         free(canon_path);
diff --git a/packages/seacas/libraries/exodus/src/ex_open_par.c b/packages/seacas/libraries/exodus/src/ex_open_par.c
index 724d301eee76..5bfad214c030 100644
--- a/packages/seacas/libraries/exodus/src/ex_open_par.c
+++ b/packages/seacas/libraries/exodus/src/ex_open_par.c
@@ -291,9 +291,9 @@ int ex_open_par_int(const char *path, int mode, int *comp_ws, int *io_ws, float
     }
 
     snprintf(errmsg, MAX_ERR_LENGTH,
-             "ERROR: failed to open %s for read/write.\n\tEither the file "
-             "does not exist,\n\tor there is a permission or file format "
-             "issue.",
+             "ERROR: failed to open %s of type %d for reading.\n\t\tThe "
+             "file does not exist, or there is a permission or file "
+             "format issue.",
              canon_path);
     ex_err(__func__, errmsg, status);
     free(canon_path);
@@ -313,7 +313,7 @@ int ex_open_par_int(const char *path, int mode, int *comp_ws, int *io_ws, float
   if (mode & EX_WRITE) { /* Appending */
     /* turn off automatic filling of netCDF variables */
     if (is_pnetcdf) {
-      if ((status = nc_redef(exoid)) != NC_NOERR) {
+      if ((status = exi_redef(exoid, __func__)) != NC_NOERR) {
         snprintf(errmsg, MAX_ERR_LENGTH, "ERROR: failed to put file id %d into define mode", exoid);
         ex_err_fn(exoid, __func__, errmsg, status);
         free(canon_path);
@@ -359,7 +359,7 @@ int ex_open_par_int(const char *path, int mode, int *comp_ws, int *io_ws, float
     }
 
     if (in_redef) {
-      if ((status = exi_leavedef(exoid, __func__)) != NC_NOERR) {
+      if ((status = nc_enddef(exoid)) != NC_NOERR) {
         free(canon_path);
         EX_FUNC_LEAVE(EX_FATAL);
       }
diff --git a/packages/seacas/libraries/exodus/src/ex_put_all_var_param_ext.c b/packages/seacas/libraries/exodus/src/ex_put_all_var_param_ext.c
index 074a79d84f88..7bcf30eb1ef9 100644
--- a/packages/seacas/libraries/exodus/src/ex_put_all_var_param_ext.c
+++ b/packages/seacas/libraries/exodus/src/ex_put_all_var_param_ext.c
@@ -144,7 +144,7 @@ int ex_put_all_var_param_ext(int exoid, const ex_var_params *vp)
                     EX_ELEM_SET, VAR_ELS_STAT, elset_stat);
 
   /* put file into define mode  */
-  if ((status = nc_redef(exoid)) != NC_NOERR) {
+  if ((status = exi_redef(exoid, __func__)) != NC_NOERR) {
     snprintf(errmsg, MAX_ERR_LENGTH, "ERROR: failed to put file id %d into define mode", exoid);
     ex_err_fn(exoid, __func__, errmsg, status);
     goto error_ret;
diff --git a/packages/seacas/libraries/exodus/src/ex_put_assemblies.c b/packages/seacas/libraries/exodus/src/ex_put_assemblies.c
index c3e1f2c398c9..a731215b546a 100644
--- a/packages/seacas/libraries/exodus/src/ex_put_assemblies.c
+++ b/packages/seacas/libraries/exodus/src/ex_put_assemblies.c
@@ -45,7 +45,7 @@ int ex_put_assemblies(int exoid, size_t count, const struct ex_assembly *assembl
       /* Assembly has not already been defined */
       /* put netcdf file into define mode  */
       if (!in_define) {
-        if ((status = nc_redef(exoid)) != NC_NOERR) {
+        if ((status = exi_redef(exoid, __func__)) != NC_NOERR) {
           snprintf(errmsg, MAX_ERR_LENGTH, "ERROR: failed to put file id %d into define mode",
                    exoid);
           ex_err_fn(exoid, __func__, errmsg, status);
diff --git a/packages/seacas/libraries/exodus/src/ex_put_attr_param.c b/packages/seacas/libraries/exodus/src/ex_put_attr_param.c
index 498d019c2df1..dd7847c7da5a 100644
--- a/packages/seacas/libraries/exodus/src/ex_put_attr_param.c
+++ b/packages/seacas/libraries/exodus/src/ex_put_attr_param.c
@@ -149,7 +149,7 @@ int ex_put_attr_param(int exoid, ex_entity_type obj_type, ex_entity_id obj_id, i
   }
 
   /* put netcdf file into define mode  */
-  if ((status = nc_redef(exoid)) != NC_NOERR) {
+  if ((status = exi_redef(exoid, __func__)) != NC_NOERR) {
     snprintf(errmsg, MAX_ERR_LENGTH, "ERROR: failed to place file id %d into define mode", exoid);
     ex_err_fn(exoid, __func__, errmsg, status);
     EX_FUNC_LEAVE(EX_FATAL);
diff --git a/packages/seacas/libraries/exodus/src/ex_put_attribute.c b/packages/seacas/libraries/exodus/src/ex_put_attribute.c
index 370cfe31ef5e..a63b09cc813f 100644
--- a/packages/seacas/libraries/exodus/src/ex_put_attribute.c
+++ b/packages/seacas/libraries/exodus/src/ex_put_attribute.c
@@ -38,7 +38,7 @@ int ex_put_double_attribute(int exoid, ex_entity_type obj_type, ex_entity_id id,
   }
 
   /* put netcdf file into define mode  */
-  if ((status = nc_redef(exoid)) != NC_NOERR) {
+  if ((status = exi_redef(exoid, __func__)) != NC_NOERR) {
     snprintf(errmsg, MAX_ERR_LENGTH, "ERROR: failed to put file id %d into define mode", exoid);
     ex_err_fn(exoid, __func__, errmsg, status);
     EX_FUNC_LEAVE(EX_FATAL);
@@ -84,7 +84,7 @@ int ex_put_integer_attribute(int exoid, ex_entity_type obj_type, ex_entity_id id
   }
 
   /* put netcdf file into define mode  */
-  if ((status = nc_redef(exoid)) != NC_NOERR) {
+  if ((status = exi_redef(exoid, __func__)) != NC_NOERR) {
     snprintf(errmsg, MAX_ERR_LENGTH, "ERROR: failed to put file id %d into define mode", exoid);
     ex_err_fn(exoid, __func__, errmsg, status);
     EX_FUNC_LEAVE(EX_FATAL);
@@ -137,7 +137,7 @@ int ex_put_text_attribute(int exoid, ex_entity_type obj_type, ex_entity_id id, c
   }
 
   /* put netcdf file into define mode  */
-  if ((status = nc_redef(exoid)) != NC_NOERR) {
+  if ((status = exi_redef(exoid, __func__)) != NC_NOERR) {
     snprintf(errmsg, MAX_ERR_LENGTH, "ERROR: failed to put file id %d into define mode", exoid);
     ex_err_fn(exoid, __func__, errmsg, status);
     EX_FUNC_LEAVE(EX_FATAL);
diff --git a/packages/seacas/libraries/exodus/src/ex_put_blobs.c b/packages/seacas/libraries/exodus/src/ex_put_blobs.c
index 5bd70b3fdd05..89c22537bb60 100644
--- a/packages/seacas/libraries/exodus/src/ex_put_blobs.c
+++ b/packages/seacas/libraries/exodus/src/ex_put_blobs.c
@@ -29,7 +29,7 @@ int ex_put_blobs(int exoid, size_t count, const struct ex_blob *blobs)
 
   int *entlst_id = (int *)calloc(count, sizeof(int));
 
-  if ((status = nc_redef(exoid)) != NC_NOERR) {
+  if ((status = exi_redef(exoid, __func__)) != NC_NOERR) {
     snprintf(errmsg, MAX_ERR_LENGTH, "ERROR: failed to put file id %d into define mode", exoid);
     ex_err_fn(exoid, __func__, errmsg, status);
     free(entlst_id);
diff --git a/packages/seacas/libraries/exodus/src/ex_put_block_params.c b/packages/seacas/libraries/exodus/src/ex_put_block_params.c
index 3f3801513056..b6d16dd3ccd8 100644
--- a/packages/seacas/libraries/exodus/src/ex_put_block_params.c
+++ b/packages/seacas/libraries/exodus/src/ex_put_block_params.c
@@ -253,7 +253,7 @@ int ex_put_block_params(int exoid, size_t block_count, const struct ex_block *bl
   }
 
   /* put netcdf file into define mode  */
-  if ((status = nc_redef(exoid)) != NC_NOERR) {
+  if ((status = exi_redef(exoid, __func__)) != NC_NOERR) {
     snprintf(errmsg, MAX_ERR_LENGTH, "ERROR: failed to place file id %d into define mode", exoid);
     ex_err_fn(exoid, __func__, errmsg, status);
     free(blocks_to_define);
diff --git a/packages/seacas/libraries/exodus/src/ex_put_cmap_params.c b/packages/seacas/libraries/exodus/src/ex_put_cmap_params.c
index bf70211e32ad..196d1966bf7c 100644
--- a/packages/seacas/libraries/exodus/src/ex_put_cmap_params.c
+++ b/packages/seacas/libraries/exodus/src/ex_put_cmap_params.c
@@ -87,7 +87,7 @@ int ex_put_cmap_params(int exoid, const void_int *node_cmap_ids,
 
   /* Put NetCDF file into define mode */
   int status;
-  if ((status = nc_redef(exoid)) != NC_NOERR) {
+  if ((status = exi_redef(exoid, __func__)) != NC_NOERR) {
     snprintf(errmsg, MAX_ERR_LENGTH, "ERROR: failed to file ID %d into define mode", exoid);
     ex_err_fn(exoid, __func__, errmsg, status);
     EX_FUNC_LEAVE(EX_FATAL);
diff --git a/packages/seacas/libraries/exodus/src/ex_put_cmap_params_cc.c b/packages/seacas/libraries/exodus/src/ex_put_cmap_params_cc.c
index 6c6809380835..1df47f1eee80 100644
--- a/packages/seacas/libraries/exodus/src/ex_put_cmap_params_cc.c
+++ b/packages/seacas/libraries/exodus/src/ex_put_cmap_params_cc.c
@@ -215,7 +215,7 @@ file ID %d",
   } /* "if (num_e_comm_maps >0)" */
 
   /* Put NetCDF file into define mode */
-  if ((status = nc_redef(exoid)) != NC_NOERR) {
+  if ((status = exi_redef(exoid, __func__)) != NC_NOERR) {
     snprintf(errmsg, MAX_ERR_LENGTH, "ERROR: failed to put file ID %d into define mode", exoid);
     ex_err_fn(exoid, __func__, errmsg, status);
     EX_FUNC_LEAVE(EX_FATAL);
diff --git a/packages/seacas/libraries/exodus/src/ex_put_concat_all_blocks.c b/packages/seacas/libraries/exodus/src/ex_put_concat_all_blocks.c
index 53573ac67c65..f4b4a997bc78 100644
--- a/packages/seacas/libraries/exodus/src/ex_put_concat_all_blocks.c
+++ b/packages/seacas/libraries/exodus/src/ex_put_concat_all_blocks.c
@@ -205,7 +205,7 @@ int ex_put_concat_all_blocks(int exoid, const ex_block_params *param)
     EX_FUNC_LEAVE(EX_NOERR);
   }
   /* put netcdf file into define mode  */
-  if ((status = nc_redef(exoid)) != NC_NOERR) {
+  if ((status = exi_redef(exoid, __func__)) != NC_NOERR) {
     snprintf(errmsg, MAX_ERR_LENGTH, "ERROR: failed to place file id %d into define mode", exoid);
     ex_err_fn(exoid, __func__, errmsg, status);
     EX_FUNC_LEAVE(EX_FATAL);
diff --git a/packages/seacas/libraries/exodus/src/ex_put_concat_elem_block.c b/packages/seacas/libraries/exodus/src/ex_put_concat_elem_block.c
index f5c7ad17bfc4..92ce78b781b0 100644
--- a/packages/seacas/libraries/exodus/src/ex_put_concat_elem_block.c
+++ b/packages/seacas/libraries/exodus/src/ex_put_concat_elem_block.c
@@ -144,7 +144,7 @@ int ex_put_concat_elem_block(int exoid, const void_int *elem_blk_id, char *const
   }
 
   /* put netcdf file into define mode  */
-  if ((status = nc_redef(exoid)) != NC_NOERR) {
+  if ((status = exi_redef(exoid, __func__)) != NC_NOERR) {
     snprintf(errmsg, MAX_ERR_LENGTH, "ERROR: failed to place file id %d into define mode", exoid);
     ex_err_fn(exoid, __func__, errmsg, status);
     free(eb_array);
diff --git a/packages/seacas/libraries/exodus/src/ex_put_concat_sets.c b/packages/seacas/libraries/exodus/src/ex_put_concat_sets.c
index 43a8807b6361..31c59c187c80 100644
--- a/packages/seacas/libraries/exodus/src/ex_put_concat_sets.c
+++ b/packages/seacas/libraries/exodus/src/ex_put_concat_sets.c
@@ -171,7 +171,7 @@ int ex_put_concat_sets(int exoid, ex_entity_type set_type, const struct ex_set_s
   }
 
   /* put netcdf file into define mode  */
-  if ((status = nc_redef(exoid)) != NC_NOERR) {
+  if ((status = exi_redef(exoid, __func__)) != NC_NOERR) {
     snprintf(errmsg, MAX_ERR_LENGTH, "ERROR: failed to put file id %d into define mode", exoid);
     ex_err_fn(exoid, __func__, errmsg, status);
     free(set_stat);
diff --git a/packages/seacas/libraries/exodus/src/ex_put_coordinate_frames.c b/packages/seacas/libraries/exodus/src/ex_put_coordinate_frames.c
index b11c10c42a47..9e2edda44278 100644
--- a/packages/seacas/libraries/exodus/src/ex_put_coordinate_frames.c
+++ b/packages/seacas/libraries/exodus/src/ex_put_coordinate_frames.c
@@ -57,7 +57,7 @@ int ex_put_coordinate_frames(int exoid, int nframes, const void_int *cf_ids,
   /* make the definitions */
   /* go into define mode. define num_frames, num_frames9 */
   int status;
-  if ((status = nc_redef(exoid)) != NC_NOERR) {
+  if ((status = exi_redef(exoid, __func__)) != NC_NOERR) {
     snprintf(errmsg, MAX_ERR_LENGTH, "ERROR: failed to place file id %d into define mode", exoid);
     ex_err_fn(exoid, __func__, errmsg, status);
     EX_FUNC_LEAVE(EX_FATAL);
diff --git a/packages/seacas/libraries/exodus/src/ex_put_field_metadata.c b/packages/seacas/libraries/exodus/src/ex_put_field_metadata.c
index 36ad8a30f8b7..ff388de656db 100644
--- a/packages/seacas/libraries/exodus/src/ex_put_field_metadata.c
+++ b/packages/seacas/libraries/exodus/src/ex_put_field_metadata.c
@@ -32,6 +32,28 @@ static int exi_print_attribute_error(int status, const char *name, const char *a
   return EX_FATAL;
 }
 
+int ex_put_multi_field_metadata(int exoid, const ex_field field[], const int count)
+{
+  exi_persist_redef(exoid, __func__);
+  for (int i = 0; i < count; i++) {
+    if (field[i].type[0] != EX_SCALAR) {
+      int status = ex_put_field_metadata(exoid, field[i]);
+      if (status != EX_NOERR) {
+        char errmsg[MAX_ERR_LENGTH];
+        snprintf(errmsg, MAX_ERR_LENGTH,
+                 "ERROR: failed to store field metadata for field '%s' on %s with id %" PRId64
+                 " in file id %d",
+                 field[i].name, ex_name_of_object(field[i].entity_type), field[i].entity_id, exoid);
+        ex_err_fn(exoid, __func__, errmsg, status);
+        exi_persist_leavedef(exoid, __func__);
+        return EX_FATAL;
+      }
+    }
+  }
+  exi_persist_leavedef(exoid, __func__);
+  return EX_NOERR;
+}
+
 int ex_put_field_metadata(int exoid, const ex_field field)
 {
   /*
@@ -53,28 +75,38 @@ int ex_put_field_metadata(int exoid, const ex_field field)
           field.entity_id);
 #endif
 
+  exi_persist_redef(exoid, __func__);
   int          status         = 0;
   static char *field_template = "Field@%s@%s";
   char         attribute_name[NC_MAX_NAME + 1];
   sprintf(attribute_name, field_template, field.name, "type");
   if ((status = ex_put_integer_attribute(exoid, field.entity_type, field.entity_id, attribute_name,
                                          field.nesting, field.type)) != EX_NOERR) {
+    exi_persist_leavedef(exoid, __func__);
     return exi_print_attribute_error(status, field.name, "type", field.entity_type, field.entity_id,
                                      exoid, __func__);
   }
 
-  sprintf(attribute_name, field_template, field.name, "type_name");
-  if ((status = ex_put_text_attribute(exoid, field.entity_type, field.entity_id, attribute_name,
-                                      field.type_name)) != EX_NOERR) {
-    return exi_print_attribute_error(status, field.name, "type_name", field.entity_type,
-                                     field.entity_id, exoid, __func__);
+  /* Do not write if empty... */
+  if (field.type_name[0] != '\0') {
+    sprintf(attribute_name, field_template, field.name, "type_name");
+    if ((status = ex_put_text_attribute(exoid, field.entity_type, field.entity_id, attribute_name,
+                                        field.type_name)) != EX_NOERR) {
+      exi_persist_leavedef(exoid, __func__);
+      return exi_print_attribute_error(status, field.name, "type_name", field.entity_type,
+                                       field.entity_id, exoid, __func__);
+    }
   }
 
-  sprintf(attribute_name, field_template, field.name, "separator");
-  if ((status = ex_put_text_attribute(exoid, field.entity_type, field.entity_id, attribute_name,
-                                      field.component_separator)) != EX_NOERR) {
-    return exi_print_attribute_error(status, field.name, "separator", field.entity_type,
-                                     field.entity_id, exoid, __func__);
+  /* Default component_separator is '_'.  Avoid writing if that is what it is... */
+  if (field.component_separator[0] != '_' || field.nesting > 1) {
+    sprintf(attribute_name, field_template, field.name, "separator");
+    if ((status = ex_put_text_attribute(exoid, field.entity_type, field.entity_id, attribute_name,
+                                        field.component_separator)) != EX_NOERR) {
+      exi_persist_leavedef(exoid, __func__);
+      return exi_print_attribute_error(status, field.name, "separator", field.entity_type,
+                                       field.entity_id, exoid, __func__);
+    }
   }
 
   bool needs_cardinality = false;
@@ -89,11 +121,13 @@ int ex_put_field_metadata(int exoid, const ex_field field)
     if ((status = ex_put_integer_attribute(exoid, field.entity_type, field.entity_id,
                                            attribute_name, field.nesting, field.cardinality)) !=
         EX_NOERR) {
+      exi_persist_leavedef(exoid, __func__);
       return exi_print_attribute_error(status, field.name, "cardinality", field.entity_type,
                                        field.entity_id, exoid, __func__);
     }
   }
 
+  exi_persist_leavedef(exoid, __func__);
   return EX_NOERR;
 }
 
@@ -145,46 +179,56 @@ int ex_put_basis(int exoid, const ex_basis basis)
    *  } ex_basis;
    */
 
+  exi_persist_redef(exoid, __func__);
   int status;
   if ((status = exi_put_basis_attribute(exoid, basis.name, "cardinality", EX_INTEGER, 1,
                                         &basis.cardinality)) != EX_NOERR) {
+    exi_persist_leavedef(exoid, __func__);
     return exi_print_type_error(status, basis.name, "basis", "cardinality", exoid, __func__);
   }
 
   if ((status = exi_put_basis_attribute(exoid, basis.name, "subc_dim", EX_INTEGER,
                                         basis.cardinality, basis.subc_dim)) != EX_NOERR) {
+    exi_persist_leavedef(exoid, __func__);
     return exi_print_type_error(status, basis.name, "basis", "subc_dim", exoid, __func__);
   }
 
   if ((status = exi_put_basis_attribute(exoid, basis.name, "subc_ordinal", EX_INTEGER,
                                         basis.cardinality, basis.subc_ordinal)) != EX_NOERR) {
+    exi_persist_leavedef(exoid, __func__);
     return exi_print_type_error(status, basis.name, "basis", "subc_ordinal", exoid, __func__);
   }
 
   if ((status = exi_put_basis_attribute(exoid, basis.name, "subc_dof_ordinal", EX_INTEGER,
                                         basis.cardinality, basis.subc_dof_ordinal)) != EX_NOERR) {
+    exi_persist_leavedef(exoid, __func__);
     return exi_print_type_error(status, basis.name, "basis", "subc_dof_ordinal", exoid, __func__);
   }
 
   if ((status = exi_put_basis_attribute(exoid, basis.name, "subc_num_dof", EX_INTEGER,
                                         basis.cardinality, basis.subc_num_dof)) != EX_NOERR) {
+    exi_persist_leavedef(exoid, __func__);
     return exi_print_type_error(status, basis.name, "basis", "subc_num_dof", exoid, __func__);
   }
 
   if ((status = exi_put_basis_attribute(exoid, basis.name, "xi", EX_DOUBLE, basis.cardinality,
                                         basis.xi)) != EX_NOERR) {
+    exi_persist_leavedef(exoid, __func__);
     return exi_print_type_error(status, basis.name, "basis", "xi", exoid, __func__);
   }
 
   if ((status = exi_put_basis_attribute(exoid, basis.name, "eta", EX_DOUBLE, basis.cardinality,
                                         basis.eta)) != EX_NOERR) {
+    exi_persist_leavedef(exoid, __func__);
     return exi_print_type_error(status, basis.name, "basis", "eta", exoid, __func__);
   }
 
   if ((status = exi_put_basis_attribute(exoid, basis.name, "zeta", EX_DOUBLE, basis.cardinality,
                                         basis.zeta)) != EX_NOERR) {
+    exi_persist_leavedef(exoid, __func__);
     return exi_print_type_error(status, basis.name, "basis", "zeta", exoid, __func__);
   }
+  exi_persist_leavedef(exoid, __func__);
   return EX_NOERR;
 }
 
@@ -204,31 +248,38 @@ int ex_put_quadrature(int exoid, const ex_quadrature quad)
    *  } ex_quad;
    */
 
+  exi_persist_redef(exoid, __func__);
   int status;
   if ((status = exi_put_quad_attribute(exoid, quad.name, "cardinality", EX_INTEGER, 1,
                                        &quad.cardinality)) != EX_NOERR) {
+    exi_persist_leavedef(exoid, __func__);
     return exi_print_type_error(status, quad.name, "quad", "cardinality", exoid, __func__);
   }
 
   if ((status = exi_put_quad_attribute(exoid, quad.name, "xi", EX_DOUBLE, quad.cardinality,
                                        quad.xi)) != EX_NOERR) {
+    exi_persist_leavedef(exoid, __func__);
     return exi_print_type_error(status, quad.name, "quad", "xi", exoid, __func__);
   }
 
   if ((status = exi_put_quad_attribute(exoid, quad.name, "eta", EX_DOUBLE, quad.cardinality,
                                        quad.eta)) != EX_NOERR) {
+    exi_persist_leavedef(exoid, __func__);
     return exi_print_type_error(status, quad.name, "quad", "eta", exoid, __func__);
   }
 
   if ((status = exi_put_quad_attribute(exoid, quad.name, "zeta", EX_DOUBLE, quad.cardinality,
                                        quad.zeta)) != EX_NOERR) {
+    exi_persist_leavedef(exoid, __func__);
     return exi_print_type_error(status, quad.name, "quad", "zeta", exoid, __func__);
   }
 
   if ((status = exi_put_quad_attribute(exoid, quad.name, "weight", EX_DOUBLE, quad.cardinality,
                                        quad.weight)) != EX_NOERR) {
+    exi_persist_leavedef(exoid, __func__);
     return exi_print_type_error(status, quad.name, "quad", "weight", exoid, __func__);
   }
+  exi_persist_leavedef(exoid, __func__);
   return EX_NOERR;
 }
 
diff --git a/packages/seacas/libraries/exodus/src/ex_put_id_map.c b/packages/seacas/libraries/exodus/src/ex_put_id_map.c
index eaae70e01318..fb38531d5578 100644
--- a/packages/seacas/libraries/exodus/src/ex_put_id_map.c
+++ b/packages/seacas/libraries/exodus/src/ex_put_id_map.c
@@ -83,7 +83,7 @@ int ex_put_id_map(int exoid, ex_entity_type map_type, const void_int *map)
 
   /* put netcdf file into define mode  */
   if (nc_inq_varid(exoid, vmap, &mapid) != NC_NOERR) {
-    if ((status = nc_redef(exoid)) != NC_NOERR) {
+    if ((status = exi_redef(exoid, __func__)) != NC_NOERR) {
       snprintf(errmsg, MAX_ERR_LENGTH, "ERROR: failed to put file id %d into define mode", exoid);
       ex_err_fn(exoid, __func__, errmsg, status);
       EX_FUNC_LEAVE(EX_FATAL);
diff --git a/packages/seacas/libraries/exodus/src/ex_put_info.c b/packages/seacas/libraries/exodus/src/ex_put_info.c
index da69df0d83fd..4878d1d884f4 100644
--- a/packages/seacas/libraries/exodus/src/ex_put_info.c
+++ b/packages/seacas/libraries/exodus/src/ex_put_info.c
@@ -1,5 +1,5 @@
 /*
- * Copyright(C) 1999-2020, 2022 National Technology & Engineering Solutions
+ * Copyright(C) 1999-2020, 2022, 2024 National Technology & Engineering Solutions
  * of Sandia, LLC (NTESS).  Under the terms of Contract DE-NA0003525 with
  * NTESS, the U.S. Government retains certain rights in this software.
  *
@@ -95,7 +95,7 @@ int ex_put_info(int exoid, int num_info, char *const info[])
     if (status != NC_NOERR) {
 
       /* put file into define mode  */
-      if ((status = nc_redef(rootid)) != NC_NOERR) {
+      if ((status = exi_redef(rootid, __func__)) != NC_NOERR) {
         snprintf(errmsg, MAX_ERR_LENGTH, "ERROR: failed put file id %d into define mode", rootid);
         ex_err_fn(exoid, __func__, errmsg, status);
         EX_FUNC_LEAVE(EX_FATAL);
diff --git a/packages/seacas/libraries/exodus/src/ex_put_init_ext.c b/packages/seacas/libraries/exodus/src/ex_put_init_ext.c
index 6d1ecb301a56..e07e8434444b 100644
--- a/packages/seacas/libraries/exodus/src/ex_put_init_ext.c
+++ b/packages/seacas/libraries/exodus/src/ex_put_init_ext.c
@@ -247,7 +247,7 @@ int ex_put_init_ext(int exoid, const ex_init_params *model)
   }
 
   /* put file into define mode */
-  if ((status = nc_redef(exoid)) != NC_NOERR) {
+  if ((status = exi_redef(exoid, __func__)) != NC_NOERR) {
     char errmsg[MAX_ERR_LENGTH];
     snprintf(errmsg, MAX_ERR_LENGTH, "ERROR: failed to put file id %d into define mode", exoid);
     ex_err_fn(exoid, __func__, errmsg, status);
diff --git a/packages/seacas/libraries/exodus/src/ex_put_init_global.c b/packages/seacas/libraries/exodus/src/ex_put_init_global.c
index 5053d37b27ec..f6731cd1640c 100644
--- a/packages/seacas/libraries/exodus/src/ex_put_init_global.c
+++ b/packages/seacas/libraries/exodus/src/ex_put_init_global.c
@@ -60,7 +60,7 @@ int ex_put_init_global(int exoid, int64_t num_nodes_g, int64_t num_elems_g, int6
     id_type = NC_INT64;
   }
   /* Put NetCDF file into define mode */
-  if ((status = nc_redef(exoid)) != NC_NOERR) {
+  if ((status = exi_redef(exoid, __func__)) != NC_NOERR) {
     snprintf(errmsg, MAX_ERR_LENGTH, "ERROR: failed to put file ID %d into define mode", exoid);
     ex_err_fn(exoid, __func__, errmsg, status);
     EX_FUNC_LEAVE(EX_FATAL);
diff --git a/packages/seacas/libraries/exodus/src/ex_put_init_info.c b/packages/seacas/libraries/exodus/src/ex_put_init_info.c
index 0c88892b4364..29c55db5eb3e 100644
--- a/packages/seacas/libraries/exodus/src/ex_put_init_info.c
+++ b/packages/seacas/libraries/exodus/src/ex_put_init_info.c
@@ -68,7 +68,7 @@ int ex_put_init_info(int exoid, int num_proc, int num_proc_in_f, const char *fty
   }
 
   /* Put file into define mode */
-  if ((status = nc_redef(exoid)) != NC_NOERR) {
+  if ((status = exi_redef(exoid, __func__)) != NC_NOERR) {
     snprintf(errmsg, MAX_ERR_LENGTH, "ERROR: failed to put file ID %d into define mode", exoid);
     ex_err_fn(exoid, __func__, errmsg, status);
     EX_FUNC_LEAVE(EX_FATAL);
diff --git a/packages/seacas/libraries/exodus/src/ex_put_loadbal_param.c b/packages/seacas/libraries/exodus/src/ex_put_loadbal_param.c
index f5463e863747..9307850593b9 100644
--- a/packages/seacas/libraries/exodus/src/ex_put_loadbal_param.c
+++ b/packages/seacas/libraries/exodus/src/ex_put_loadbal_param.c
@@ -91,7 +91,7 @@ int ex_put_loadbal_param(int exoid, int64_t num_int_nodes, int64_t num_bor_nodes
   }
 
   /* Put NetCDF file into define mode */
-  if ((status = nc_redef(exoid)) != NC_NOERR) {
+  if ((status = exi_redef(exoid, __func__)) != NC_NOERR) {
     snprintf(errmsg, MAX_ERR_LENGTH, "ERROR: failed to put file id %d into define mode", exoid);
     ex_err_fn(exoid, __func__, errmsg, status);
     EX_FUNC_LEAVE(EX_FATAL);
diff --git a/packages/seacas/libraries/exodus/src/ex_put_loadbal_param_cc.c b/packages/seacas/libraries/exodus/src/ex_put_loadbal_param_cc.c
index ed64526b4934..dc1d9dc35865 100644
--- a/packages/seacas/libraries/exodus/src/ex_put_loadbal_param_cc.c
+++ b/packages/seacas/libraries/exodus/src/ex_put_loadbal_param_cc.c
@@ -120,7 +120,7 @@ int ex_put_loadbal_param_cc(int exoid, const void_int *num_int_nodes, const void
   }
 
   /* Put NetCDF file into define mode */
-  if ((status = nc_redef(exoid)) != NC_NOERR) {
+  if ((status = exi_redef(exoid, __func__)) != NC_NOERR) {
     snprintf(errmsg, MAX_ERR_LENGTH, "ERROR: failed to put file id %d into define mode", exoid);
     ex_err_fn(exoid, __func__, errmsg, status);
     EX_FUNC_LEAVE(EX_FATAL);
diff --git a/packages/seacas/libraries/exodus/src/ex_put_map.c b/packages/seacas/libraries/exodus/src/ex_put_map.c
index 9861092f0553..f03881a42f21 100644
--- a/packages/seacas/libraries/exodus/src/ex_put_map.c
+++ b/packages/seacas/libraries/exodus/src/ex_put_map.c
@@ -75,7 +75,7 @@ int ex_put_map(int exoid, const void_int *elem_map)
   }
 
   /* put netcdf file into define mode  */
-  if ((status = nc_redef(exoid)) != NC_NOERR) {
+  if ((status = exi_redef(exoid, __func__)) != NC_NOERR) {
     snprintf(errmsg, MAX_ERR_LENGTH, "ERROR: failed to put file id %d into define mode", exoid);
     ex_err_fn(exoid, __func__, errmsg, status);
     EX_FUNC_LEAVE(EX_FATAL);
diff --git a/packages/seacas/libraries/exodus/src/ex_put_map_param.c b/packages/seacas/libraries/exodus/src/ex_put_map_param.c
index f9d30aa53e45..8347e5c4b273 100644
--- a/packages/seacas/libraries/exodus/src/ex_put_map_param.c
+++ b/packages/seacas/libraries/exodus/src/ex_put_map_param.c
@@ -73,7 +73,7 @@ int ex_put_map_param(int exoid, int num_node_maps, int num_elem_maps)
     }
 
     /* put file into define mode */
-    if ((status = nc_redef(exoid)) != NC_NOERR) {
+    if ((status = exi_redef(exoid, __func__)) != NC_NOERR) {
       snprintf(errmsg, MAX_ERR_LENGTH, "ERROR: failed to put file id %d into define mode", exoid);
       ex_err_fn(exoid, __func__, errmsg, status);
       EX_FUNC_LEAVE(EX_FATAL);
diff --git a/packages/seacas/libraries/exodus/src/ex_put_name.c b/packages/seacas/libraries/exodus/src/ex_put_name.c
index 0c161ab38533..c0dc4a93af31 100644
--- a/packages/seacas/libraries/exodus/src/ex_put_name.c
+++ b/packages/seacas/libraries/exodus/src/ex_put_name.c
@@ -39,7 +39,7 @@ int exi_put_assembly_name(int exoid, ex_entity_type obj_type, ex_entity_id entit
   char errmsg[MAX_ERR_LENGTH];
   if (nc_inq_varid(exoid, VAR_ENTITY_ASSEMBLY(entity_id), &entlst_id) == NC_NOERR) {
     int status;
-    if ((status = nc_redef(exoid)) != NC_NOERR) {
+    if ((status = exi_redef(exoid, __func__)) != NC_NOERR) {
       snprintf(errmsg, MAX_ERR_LENGTH, "ERROR: failed to put file id %d into define mode", exoid);
       ex_err_fn(exoid, __func__, errmsg, status);
       EX_FUNC_LEAVE(EX_FATAL);
diff --git a/packages/seacas/libraries/exodus/src/ex_put_num_map.c b/packages/seacas/libraries/exodus/src/ex_put_num_map.c
index b4aa483fdc06..85a5c9d73f67 100644
--- a/packages/seacas/libraries/exodus/src/ex_put_num_map.c
+++ b/packages/seacas/libraries/exodus/src/ex_put_num_map.c
@@ -190,7 +190,7 @@ int ex_put_num_map(int exoid, ex_entity_type map_type, ex_entity_id map_id, cons
       EX_FUNC_LEAVE(EX_FATAL);
     }
 
-    if ((status = nc_redef(exoid)) != NC_NOERR) {
+    if ((status = exi_redef(exoid, __func__)) != NC_NOERR) {
       snprintf(errmsg, MAX_ERR_LENGTH, "ERROR: failed to place file id %d into define mode", exoid);
       ex_err_fn(exoid, __func__, errmsg, status);
       EX_FUNC_LEAVE(EX_FATAL);
diff --git a/packages/seacas/libraries/exodus/src/ex_put_partial_id_map.c b/packages/seacas/libraries/exodus/src/ex_put_partial_id_map.c
index 7c1ffcdab5f6..6a97fd8ee04a 100644
--- a/packages/seacas/libraries/exodus/src/ex_put_partial_id_map.c
+++ b/packages/seacas/libraries/exodus/src/ex_put_partial_id_map.c
@@ -106,7 +106,7 @@ int ex_put_partial_id_map(int exoid, ex_entity_type map_type, int64_t start_enti
 
   /* define the map if it doesn't already exist... */
   if (nc_inq_varid(exoid, vmap, &mapid) != NC_NOERR) {
-    if ((status = nc_redef(exoid)) != NC_NOERR) {
+    if ((status = exi_redef(exoid, __func__)) != NC_NOERR) {
       snprintf(errmsg, MAX_ERR_LENGTH, "ERROR: failed to put file id %d into define mode", exoid);
       ex_err_fn(exoid, __func__, errmsg, status);
       EX_FUNC_LEAVE(EX_FATAL);
diff --git a/packages/seacas/libraries/exodus/src/ex_put_partial_var.c b/packages/seacas/libraries/exodus/src/ex_put_partial_var.c
index 8eabaae831ed..bc62bca91732 100644
--- a/packages/seacas/libraries/exodus/src/ex_put_partial_var.c
+++ b/packages/seacas/libraries/exodus/src/ex_put_partial_var.c
@@ -127,7 +127,7 @@ static int exi_look_up_var(int exoid, ex_entity_type var_type, int var_index, ex
                         ex_name_of_object(var_type), &num_entity, &numobjdim, __func__);
 
       /*    variable doesn't exist so put file into define mode  */
-      if ((status = nc_redef(exoid)) != NC_NOERR) {
+      if ((status = exi_redef(exoid, __func__)) != NC_NOERR) {
         snprintf(errmsg, MAX_ERR_LENGTH, "ERROR: failed to put file id %d into define mode", exoid);
         ex_err_fn(exoid, __func__, errmsg, status);
         return (EX_FATAL);
diff --git a/packages/seacas/libraries/exodus/src/ex_put_prop.c b/packages/seacas/libraries/exodus/src/ex_put_prop.c
index 6b1a86598a32..9300d2fb3026 100644
--- a/packages/seacas/libraries/exodus/src/ex_put_prop.c
+++ b/packages/seacas/libraries/exodus/src/ex_put_prop.c
@@ -152,7 +152,7 @@ int ex_put_prop(int exoid, ex_entity_type obj_type, ex_entity_id obj_id, const c
     name_length = ex_inquire_int(exoid, EX_INQ_DB_MAX_ALLOWED_NAME_LENGTH) + 1;
 
     /* put netcdf file into define mode  */
-    if ((status = nc_redef(exoid)) != NC_NOERR) {
+    if ((status = exi_redef(exoid, __func__)) != NC_NOERR) {
       snprintf(errmsg, MAX_ERR_LENGTH, "ERROR: failed to place file id %d into define mode", exoid);
       ex_err_fn(exoid, __func__, errmsg, status);
       EX_FUNC_LEAVE(EX_FATAL);
diff --git a/packages/seacas/libraries/exodus/src/ex_put_prop_array.c b/packages/seacas/libraries/exodus/src/ex_put_prop_array.c
index 1e35e2197ab8..c49cedcc5381 100644
--- a/packages/seacas/libraries/exodus/src/ex_put_prop_array.c
+++ b/packages/seacas/libraries/exodus/src/ex_put_prop_array.c
@@ -144,7 +144,7 @@ int ex_put_prop_array(int exoid, ex_entity_type obj_type, const char *prop_name,
   if (!found) {
 
     /* put netcdf file into define mode  */
-    if ((status = nc_redef(exoid)) != NC_NOERR) {
+    if ((status = exi_redef(exoid, __func__)) != NC_NOERR) {
       snprintf(errmsg, MAX_ERR_LENGTH, "ERROR: failed to place file id %d into define mode", exoid);
       ex_err_fn(exoid, __func__, errmsg, status);
       EX_FUNC_LEAVE(EX_FATAL);
diff --git a/packages/seacas/libraries/exodus/src/ex_put_prop_names.c b/packages/seacas/libraries/exodus/src/ex_put_prop_names.c
index d88b2aeccb76..bcf063f05012 100644
--- a/packages/seacas/libraries/exodus/src/ex_put_prop_names.c
+++ b/packages/seacas/libraries/exodus/src/ex_put_prop_names.c
@@ -130,7 +130,7 @@ int ex_put_prop_names(int exoid, ex_entity_type obj_type, int num_props, char **
   nc_set_fill(exoid, NC_FILL, &oldfill); /* fill with zeros per routine spec */
 
   /* put netcdf file into define mode  */
-  if ((status = nc_redef(exoid)) != NC_NOERR) {
+  if ((status = exi_redef(exoid, __func__)) != NC_NOERR) {
     snprintf(errmsg, MAX_ERR_LENGTH, "ERROR: failed to place file id %d into define mode", exoid);
     ex_err_fn(exoid, __func__, errmsg, status);
     EX_FUNC_LEAVE(EX_FATAL);
diff --git a/packages/seacas/libraries/exodus/src/ex_put_qa.c b/packages/seacas/libraries/exodus/src/ex_put_qa.c
index 1b66067c9e63..a4efa3793670 100644
--- a/packages/seacas/libraries/exodus/src/ex_put_qa.c
+++ b/packages/seacas/libraries/exodus/src/ex_put_qa.c
@@ -1,5 +1,5 @@
 /*
- * Copyright(C) 1999-2020, 2022 National Technology & Engineering Solutions
+ * Copyright(C) 1999-2020, 2022, 2024 National Technology & Engineering Solutions
  * of Sandia, LLC (NTESS).  Under the terms of Contract DE-NA0003525 with
  * NTESS, the U.S. Government retains certain rights in this software.
  *
@@ -86,7 +86,7 @@ int ex_put_qa(int exoid, int num_qa_records, char *qa_record[][4])
     if (status != NC_NOERR) {
 
       /*   put file into define mode  */
-      if ((status = nc_redef(rootid)) != NC_NOERR) {
+      if ((status = exi_redef(rootid, __func__)) != NC_NOERR) {
         snprintf(errmsg, MAX_ERR_LENGTH, "ERROR: failed to put file id %d into define mode",
                  rootid);
         ex_err_fn(exoid, __func__, errmsg, status);
diff --git a/packages/seacas/libraries/exodus/src/ex_put_reduction_variable_param.c b/packages/seacas/libraries/exodus/src/ex_put_reduction_variable_param.c
index 2f2f4ac8a661..d3d28c85685d 100644
--- a/packages/seacas/libraries/exodus/src/ex_put_reduction_variable_param.c
+++ b/packages/seacas/libraries/exodus/src/ex_put_reduction_variable_param.c
@@ -165,7 +165,7 @@ int ex_put_reduction_variable_param(int exoid, ex_entity_type obj_type, int num_
   }
 
   /* put file into define mode  */
-  if ((status = nc_redef(exoid)) != NC_NOERR) {
+  if ((status = exi_redef(exoid, __func__)) != NC_NOERR) {
     snprintf(errmsg, MAX_ERR_LENGTH, "ERROR: failed to put file id %d into define mode", exoid);
     ex_err_fn(exoid, __func__, errmsg, status);
     EX_FUNC_LEAVE(EX_FATAL);
diff --git a/packages/seacas/libraries/exodus/src/ex_put_reduction_vars.c b/packages/seacas/libraries/exodus/src/ex_put_reduction_vars.c
index b8b97e905628..f39948bcd026 100644
--- a/packages/seacas/libraries/exodus/src/ex_put_reduction_vars.c
+++ b/packages/seacas/libraries/exodus/src/ex_put_reduction_vars.c
@@ -84,7 +84,7 @@ static int exi_look_up_var(int exoid, ex_entity_type var_type, ex_entity_id obj_
       }
 
       /*    variable doesn't exist so put file into define mode  */
-      if ((status = nc_redef(exoid)) != NC_NOERR) {
+      if ((status = exi_redef(exoid, __func__)) != NC_NOERR) {
         snprintf(errmsg, MAX_ERR_LENGTH, "ERROR: failed to put file id %d into define mode", exoid);
         ex_err_fn(exoid, __func__, errmsg, status);
         return (EX_FATAL);
diff --git a/packages/seacas/libraries/exodus/src/ex_put_sets.c b/packages/seacas/libraries/exodus/src/ex_put_sets.c
index 0a81e9439bec..772994646260 100644
--- a/packages/seacas/libraries/exodus/src/ex_put_sets.c
+++ b/packages/seacas/libraries/exodus/src/ex_put_sets.c
@@ -96,7 +96,7 @@ int ex_put_sets(int exoid, size_t set_count, const struct ex_set *sets)
 
   if (needs_define > 0) {
     /* put netcdf file into define mode  */
-    if ((status = nc_redef(exoid)) != NC_NOERR) {
+    if ((status = exi_redef(exoid, __func__)) != NC_NOERR) {
       snprintf(errmsg, MAX_ERR_LENGTH, "ERROR: failed to put file id %d into define mode", exoid);
       ex_err_fn(exoid, __func__, errmsg, status);
       free(sets_to_define);
diff --git a/packages/seacas/libraries/exodus/src/ex_put_truth_table.c b/packages/seacas/libraries/exodus/src/ex_put_truth_table.c
index ccc89a1b2155..09cb4e6973d8 100644
--- a/packages/seacas/libraries/exodus/src/ex_put_truth_table.c
+++ b/packages/seacas/libraries/exodus/src/ex_put_truth_table.c
@@ -236,7 +236,7 @@ int ex_put_truth_table(int exoid, ex_entity_type obj_type, int num_blk, int num_
   }
 
   /* put netcdf file into define mode  */
-  if ((status = nc_redef(exoid)) != NC_NOERR) {
+  if ((status = exi_redef(exoid, __func__)) != NC_NOERR) {
     free(stat_vals);
     snprintf(errmsg, MAX_ERR_LENGTH, "ERROR: failed to put file id %d into define mode", exoid);
     ex_err_fn(exoid, __func__, errmsg, status);
diff --git a/packages/seacas/libraries/exodus/src/ex_put_var_multi_time.c b/packages/seacas/libraries/exodus/src/ex_put_var_multi_time.c
index 821aec23ef59..a34123f5fb8c 100644
--- a/packages/seacas/libraries/exodus/src/ex_put_var_multi_time.c
+++ b/packages/seacas/libraries/exodus/src/ex_put_var_multi_time.c
@@ -128,7 +128,7 @@ static int exi_look_up_var(int exoid, ex_entity_type var_type, int var_index, ex
                         ex_name_of_object(var_type), &num_entity, &numobjdim, __func__);
 
       /*    variable doesn't exist so put file into define mode  */
-      if ((status = nc_redef(exoid)) != NC_NOERR) {
+      if ((status = exi_redef(exoid, __func__)) != NC_NOERR) {
         snprintf(errmsg, MAX_ERR_LENGTH, "ERROR: failed to put file id %d into define mode", exoid);
         ex_err_fn(exoid, __func__, errmsg, status);
         return EX_FATAL;
diff --git a/packages/seacas/libraries/exodus/src/ex_put_variable_param.c b/packages/seacas/libraries/exodus/src/ex_put_variable_param.c
index ed896f4a8c67..e19a10833f5f 100644
--- a/packages/seacas/libraries/exodus/src/ex_put_variable_param.c
+++ b/packages/seacas/libraries/exodus/src/ex_put_variable_param.c
@@ -174,7 +174,7 @@ int ex_put_variable_param(int exoid, ex_entity_type obj_type, int num_vars)
   }
 
   /* put file into define mode  */
-  if ((status = nc_redef(exoid)) != NC_NOERR) {
+  if ((status = exi_redef(exoid, __func__)) != NC_NOERR) {
     snprintf(errmsg, MAX_ERR_LENGTH, "ERROR: failed to put file id %d into define mode", exoid);
     ex_err_fn(exoid, __func__, errmsg, status);
     EX_FUNC_LEAVE(EX_FATAL);
diff --git a/packages/seacas/libraries/exodus/src/ex_update.c b/packages/seacas/libraries/exodus/src/ex_update.c
index 02e2f8a93003..52b0d9101391 100644
--- a/packages/seacas/libraries/exodus/src/ex_update.c
+++ b/packages/seacas/libraries/exodus/src/ex_update.c
@@ -1,5 +1,5 @@
 /*
- * Copyright(C) 1999-2021 National Technology & Engineering Solutions
+ * Copyright(C) 1999-2021, 2024 National Technology & Engineering Solutions
  * of Sandia, LLC (NTESS).  Under the terms of Contract DE-NA0003525 with
  * NTESS, the U.S. Government retains certain rights in this software.
  *
@@ -20,7 +20,7 @@
 
 #include "exodusII.h"     // for ex_err, etc
 #include "exodusII_int.h" // for EX_FATAL, EX_NOERR
-
+#include <assert.h>
 /*!
  * \ingroup Utilities
  * updates an opened EXODUS file (or EXODUS history file)
@@ -35,6 +35,11 @@ int ex_update(int exoid)
     EX_FUNC_LEAVE(EX_FATAL);
   }
 
+#ifndef NDEBUG
+  struct exi_file_item *file = exi_find_file_item(exoid);
+  assert(!file->in_define_mode && file->persist_define_mode == 0);
+#endif
+
   int status;
   if ((status = nc_sync(exoid)) != NC_NOERR) {
     char errmsg[MAX_ERR_LENGTH];
diff --git a/packages/seacas/libraries/exodus/src/ex_utils.c b/packages/seacas/libraries/exodus/src/ex_utils.c
index e23c6007b10f..0c33d625a32f 100644
--- a/packages/seacas/libraries/exodus/src/ex_utils.c
+++ b/packages/seacas/libraries/exodus/src/ex_utils.c
@@ -1777,16 +1777,114 @@ void exi_compress_variable(int exoid, int varid, int type)
   \internal
   \undoc
 */
-int exi_leavedef(int exoid, const char *call_rout)
+int exi_leavedef(int exoid, const char *call_func)
 {
   int status;
 
-  if ((status = nc_enddef(exoid)) != NC_NOERR) {
+  struct exi_file_item *file = exi_find_file_item(exoid);
+  if (!file) {
     char errmsg[MAX_ERR_LENGTH];
-    snprintf(errmsg, MAX_ERR_LENGTH, "ERROR: failed to complete definition for file id %d", exoid);
-    ex_err_fn(exoid, call_rout, errmsg, status);
+    snprintf(errmsg, MAX_ERR_LENGTH, "ERROR: unknown file id %d for %s called from %s.", exoid,
+             __func__, call_func);
+    ex_err_fn(exoid, __func__, errmsg, EX_BADFILEID);
+    return EX_FATAL;
+  }
 
-    return (EX_FATAL);
+  if (!file->persist_define_mode && file->in_define_mode) {
+    if ((status = nc_enddef(exoid)) != NC_NOERR) {
+      char errmsg[MAX_ERR_LENGTH];
+      snprintf(errmsg, MAX_ERR_LENGTH, "ERROR: failed to complete definition for file id %d",
+               exoid);
+      ex_err_fn(exoid, call_func, errmsg, status);
+
+      return (EX_FATAL);
+    }
+    file->in_define_mode = 0;
+  }
+  return (EX_NOERR);
+}
+
+int exi_redef(int exoid, const char *call_func)
+{
+  int status;
+
+  struct exi_file_item *file = exi_find_file_item(exoid);
+
+  if (!file) {
+    char errmsg[MAX_ERR_LENGTH];
+    snprintf(errmsg, MAX_ERR_LENGTH, "ERROR: unknown file id %d for %s called from %s.", exoid,
+             __func__, call_func);
+    ex_err_fn(exoid, __func__, errmsg, EX_BADFILEID);
+    return EX_FATAL;
+  }
+
+  if (!file->in_define_mode) {
+    if ((status = nc_redef(exoid)) != NC_NOERR) {
+      char errmsg[MAX_ERR_LENGTH];
+      snprintf(errmsg, MAX_ERR_LENGTH,
+               "ERROR: failed to put file %d into definition mode in exi_redef called from %s",
+               exoid, call_func);
+      ex_err_fn(exoid, __func__, errmsg, status);
+      return EX_FATAL;
+    }
+    file->in_define_mode = 1;
+  }
+  return EX_NOERR;
+}
+
+int exi_persist_redef(int exoid, const char *call_func)
+{
+  int status;
+
+  struct exi_file_item *file = exi_find_file_item(exoid);
+
+  if (!file) {
+    char errmsg[MAX_ERR_LENGTH];
+    snprintf(errmsg, MAX_ERR_LENGTH, "ERROR: unknown file id %d for %s called from %s.", exoid,
+             __func__, call_func);
+    ex_err_fn(exoid, __func__, errmsg, EX_BADFILEID);
+    return EX_FATAL;
+  }
+
+  if ((++file->persist_define_mode == 1) && !file->in_define_mode) {
+    if ((status = nc_redef(exoid)) != NC_NOERR) {
+      char errmsg[MAX_ERR_LENGTH];
+      snprintf(
+          errmsg, MAX_ERR_LENGTH,
+          "ERROR: failed to put file %d into definition mode in exi_persist_redef called from %s",
+          exoid, call_func);
+      ex_err_fn(exoid, __func__, errmsg, status);
+      return EX_FATAL;
+    }
+    file->in_define_mode = 1;
+  }
+  return EX_NOERR;
+}
+
+int exi_persist_leavedef(int exoid, const char *call_func)
+{
+  int status;
+
+  struct exi_file_item *file = exi_find_file_item(exoid);
+  if (!file) {
+    char errmsg[MAX_ERR_LENGTH];
+    snprintf(errmsg, MAX_ERR_LENGTH, "ERROR: unknown file id %d for %s called from %s.", exoid,
+             __func__, call_func);
+    ex_err_fn(exoid, __func__, errmsg, EX_BADFILEID);
+    return EX_FATAL;
+  }
+
+  if ((file->persist_define_mode-- == 1) && file->in_define_mode) {
+    if ((status = nc_enddef(exoid)) != NC_NOERR) {
+      char errmsg[MAX_ERR_LENGTH];
+      snprintf(errmsg, MAX_ERR_LENGTH, "ERROR: failed to complete definition for file id %d",
+               exoid);
+      ex_err_fn(exoid, call_func, errmsg, status);
+
+      return (EX_FATAL);
+    }
+    file->in_define_mode      = 0;
+    file->persist_define_mode = 0;
   }
   return (EX_NOERR);
 }
@@ -2090,9 +2188,16 @@ int exi_handle_mode(unsigned int my_mode, int is_parallel, int run_version)
    * unless specified differently via environment.
    */
   {
-    char *option = getenv("EXODUS_VERBOSE");
-    if (option != NULL) {
-      exoptval = EX_VERBOSE;
+    if (exoptval != EX_VERBOSE) {
+      /* Avoid getenv call if already in verbose mode */
+      char *option = getenv("EXODUS_VERBOSE");
+      if (option != NULL) {
+        exoptval = EX_VERBOSE;
+        if (option[0] != 'q') {
+          fprintf(stderr, "EXODUS: Setting EX_VERBOSE mode since EXODUS_VERBOSE environment "
+                          "variable is set.\n");
+        }
+      }
     }
     ex_opts(exoptval); /* call required to set ncopts first time through */
   }
diff --git a/packages/seacas/libraries/exodus/test/testall.in b/packages/seacas/libraries/exodus/test/testall.in
index 1e28a043b67f..889cf15434a0 100755
--- a/packages/seacas/libraries/exodus/test/testall.in
+++ b/packages/seacas/libraries/exodus/test/testall.in
@@ -357,8 +357,8 @@ echo "begin testwt-field-metadata" >> test.output
 ${PREFIX} ${BINDIR}/testwt-field-metadata${SUFFIX} >> test.output
 ret_status=$((ret_status+$?))
 # Filter out the "maximum_name_length" attribute. Moves around in ncdump output for nc4 vs nc3
-#${NCDUMP} -d5,5 test-field-metadata.exo | grep @ |sort | ${DIFF} - ${SRCDIR}/testwt-field-metadata.dmp | tee testwt-field-metadata.res
-#ret_status=$((ret_status+${PIPESTATUS[0]}+${PIPESTATUS[3]}))
+${NCDUMP} -d5,5 test-field-metadata.exo | grep @ |sort | ${DIFF} - ${SRCDIR}/testwt-field-metadata.dmp | tee testwt-field-metadata.res
+ret_status=$((ret_status+${PIPESTATUS[0]}+${PIPESTATUS[3]}))
 echo "end testwt-field-metadata, status = $ret_status" >> test.output
 
 # NOTE: netcdf-4 can put attributes in different order, so in that
diff --git a/packages/seacas/libraries/exodus/test/testwt-field-metadata.dmp b/packages/seacas/libraries/exodus/test/testwt-field-metadata.dmp
index 9b9e075aa8b9..37e75ddeb6e9 100644
--- a/packages/seacas/libraries/exodus/test/testwt-field-metadata.dmp
+++ b/packages/seacas/libraries/exodus/test/testwt-field-metadata.dmp
@@ -25,10 +25,8 @@
 		:Quad@2x2x2@zeta = -0.57735, -0.57735, -0.57735, -0.57735, 0.57735, 0.57735, 0.57735, 0.57735 ;
 		connect1:Field@Disp@separator = "" ;
 		connect1:Field@Disp@type = 8 ;
-		connect1:Field@Disp@type_name = "" ;
 		connect1:Field@Velocity@separator = "%" ;
 		connect1:Field@Velocity@type = 8 ;
-		connect1:Field@Velocity@type_name = "" ;
 		connect2:Field@Curl@separator = "@" ;
 		connect2:Field@Curl@type = 4 ;
 		connect2:Field@Curl@type_name = "2x2x2" ;
@@ -42,10 +40,8 @@
 		connect2:Field@Species@type_name = ",1x2x1" ;
 		coor_names:Field@Disp@separator = "" ;
 		coor_names:Field@Disp@type = 8 ;
-		coor_names:Field@Disp@type_name = "" ;
 		coor_names:Field@Velocity@separator = "%" ;
 		coor_names:Field@Velocity@type = 8 ;
-		coor_names:Field@Velocity@type_name = "" ;
   "Curl@1",
   "Curl@2",
   "Curl@3",
diff --git a/packages/seacas/libraries/exodus/test/testwt-field-metadata2.c b/packages/seacas/libraries/exodus/test/testwt-field-metadata2.c
deleted file mode 100644
index ffa23d9513d0..000000000000
--- a/packages/seacas/libraries/exodus/test/testwt-field-metadata2.c
+++ /dev/null
@@ -1,214 +0,0 @@
-/*
- * Copyright(C) 2022, 2023, 2024 National Technology & Engineering Solutions
- * of Sandia, LLC (NTESS).  Under the terms of Contract DE-NA0003525 with
- * NTESS, the U.S. Government retains certain rights in this software.
- *
- * See packages/seacas/LICENSE for details
- */
-
-#include <assert.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-
-#include "exodusII.h"
-
-#define STRINGIFY(x) #x
-#define TOSTRING(x)  STRINGIFY(x)
-
-#define EXCHECK(funcall)                                                                           \
-  do {                                                                                             \
-    int error = (funcall);                                                                         \
-    printf("after %s, error = %d\n", TOSTRING(funcall), error);                                    \
-    if (error != EX_NOERR) {                                                                       \
-      fprintf(stderr, "Error calling %s\n", TOSTRING(funcall));                                    \
-      ex_close(exoid);                                                                             \
-      exit(-1);                                                                                    \
-    }                                                                                              \
-  } while (0)
-
-int main(int argc, char **argv)
-{
-  ex_opts(EX_VERBOSE);
-
-  /* Specify compute and i/o word size */
-  int CPU_word_size = 8;
-  int IO_word_size  = 8;
-
-  /* create EXODUS II file */
-  int exoid = ex_create("test-field-metadata.exo", /* filename path */
-                        EX_CLOBBER,                /* create mode */
-                        &CPU_word_size,            /* CPU double word size in bytes */
-                        &IO_word_size);            /* I/O double word size in bytes */
-  printf("after ex_create for test.exo, exoid = %d\n", exoid);
-  printf(" cpu word size: %d io word size: %d\n", CPU_word_size, IO_word_size);
-
-  int num_elem_blk = 3;
-  {
-    ex_init_params par = {.num_dim       = 3,
-                          .num_nodes     = 1,
-                          .num_elem      = 7,
-                          .num_elem_blk  = num_elem_blk,
-                          .num_node_sets = 0,
-                          .num_side_sets = 0,
-                          .num_assembly  = 0};
-
-    char *title = "This is a test";
-    ex_copy_string(par.title, title, MAX_LINE_LENGTH + 1);
-    EXCHECK(ex_put_init_ext(exoid, &par));
-  }
-
-  double coord[] = {0.0};
-  EXCHECK(ex_put_coord(exoid, coord, coord, coord));
-
-  /* ======================================================================== */
-  /* write element block parameters */
-  struct ex_block blocks[num_elem_blk];
-  for (int i = 0; i < num_elem_blk; i++) {
-    blocks[i] = (ex_block){.type = EX_ELEM_BLOCK, .num_entry = 1, .id = i + 10};
-    ex_copy_string(blocks[i].topology, "sphere", MAX_STR_LENGTH + 1);
-    blocks[i].num_nodes_per_entry = 1;
-  }
-
-  EXCHECK(ex_put_block_params(exoid, num_elem_blk, blocks));
-
-  int connect[] = {1};
-  for (int i = 0; i < num_elem_blk; i++) {
-    EXCHECK(ex_put_conn(exoid, EX_ELEM_BLOCK, blocks[i].id, connect, NULL, NULL));
-  }
-
-  /* Write element block names */
-  for (int i = 0; i < num_elem_blk; i++) {
-    char block_names[32];
-    sprintf(block_names, "block_%c", i + 'A');
-    EXCHECK(ex_put_name(exoid, EX_ELEM_BLOCK, blocks[i].id, block_names));
-  }
-
-  {
-    int units[] = {1, 0, 0, -1};
-
-    EXCHECK(ex_put_integer_attribute(exoid, EX_ELEM_BLOCK, 11, "Units", 4, units));
-    EXCHECK(ex_put_text_attribute(exoid, EX_GLOBAL, 0, "SOLID_MODEL", "STEP-X-43-1547836-Rev 0"));
-  }
-
-  /* ======================================================================== */
-  /* Transient Variables */
-  char *var_names[] = {
-      "DispX",        "DispY",        "DispZ",        "Velocity%X",   "Velocity%Y",
-      "Velocity%Z",   "Gradient-X$1",
-      "Gradient-Y$1", "Gradient-Z$1", "Gradient-X$2", "Gradient-Y$2", "Gradient-Z$2",
-      "Gradient-X$3", "Gradient-Y$3", "Gradient-Z$3", "Gradient-X$4", "Gradient-Y$4",
-      "Gradient-Z$4", "Gradient-X$5", "Gradient-Y$5", "Gradient-Z$5", "Gradient-X$6",
-      "Gradient-Y$6", "Gradient-Z$6", "Gradient-X$7", "Gradient-Y$7", "Gradient-Z$7",
-      "Gradient-X$8", "Gradient-Y$8", "Gradient-Z$8", "Gradient-X$9", "Gradient-Y$9", "Gradient-Z$9", "Curl@1",       "Curl@2",
-      "Curl@3",       "Curl@4",       "Curl@5",       "Curl@6",       "Curl@7",
-      "Curl@8",       "User_h2o",     "User_gas",     "User_ch4",     "User_methane"};
-  int num_block_vars = sizeof(var_names) / sizeof(var_names[0]);
-  int num_node_vars  = 6;
-
-  EXCHECK(ex_put_variable_param(exoid, EX_ELEM_BLOCK, num_block_vars));
-  EXCHECK(ex_put_variable_names(exoid, EX_ELEM_BLOCK, num_block_vars, var_names));
-  EXCHECK(ex_put_variable_param(exoid, EX_NODAL, num_node_vars));
-  EXCHECK(ex_put_variable_names(exoid, EX_NODAL, num_node_vars, var_names));
-
-  int vname = 0;
-  {
-    struct ex_field field = (ex_field){.entity_type            = EX_ELEM_BLOCK,
-                                       .entity_id              = blocks[0].id,
-                                       .name                   = "Disp",
-                                       .type                   = {EX_VECTOR_3D},
-                                       .nesting                = 1,
-                                       .component_separator[0] = 0};
-    EXCHECK(ex_put_field_metadata(exoid, field));
-
-    /* Put same field on the nodes... */
-    field.entity_type = EX_NODAL;
-    EXCHECK(ex_put_field_metadata(exoid, field));
-
-    int cardinality =
-        field.cardinality[0] != 0 ? field.cardinality[0] : ex_field_cardinality(field.type[0]);
-    for (int i = 0; i < cardinality; i++) {
-      const char *name = ex_component_field_name(&field, (int[]){i + 1});
-      assert(strcmp(var_names[vname++], name) == 0);
-    }
-  }
-
-  {
-    struct ex_field field = (ex_field){.entity_type            = EX_ELEM_BLOCK,
-                                       .entity_id              = blocks[0].id,
-                                       .name                   = "Velocity",
-                                       .type                   = {EX_VECTOR_3D},
-                                       .nesting                = 1,
-                                       .component_separator[0] = '%'};
-    EXCHECK(ex_put_field_metadata(exoid, field));
-
-    /* Put same field on the nodes... */
-    field.entity_type = EX_NODAL;
-    EXCHECK(ex_put_field_metadata(exoid, field));
-
-    int cardinality =
-        field.cardinality[0] != 0 ? field.cardinality[0] : ex_field_cardinality(field.type[0]);
-    for (int i = 0; i < cardinality; i++) {
-      const char *name = ex_component_field_name(&field, (int[]){i + 1});
-      assert(strcmp(var_names[vname++], name) == 0);
-    }
-  }
-
-  {
-    struct ex_field field = (ex_field){.entity_type         = EX_ELEM_BLOCK,
-                                       .entity_id           = blocks[1].id,
-                                       .name                = "Gradient",
-                                       .type                = {EX_VECTOR_3D, EX_FIELD_TYPE_SEQUENCE},
-                                       .nesting             = 2,
-                                       .cardinality         = {0,9},
-                                       .component_separator = {'-', '$'}};
-    EXCHECK(ex_put_field_metadata(exoid, field));
-
-    struct ex_field field2 = (ex_field){.entity_type         = EX_ELEM_BLOCK,
-                                        .entity_id           = blocks[1].id,
-                                        .name                = "Curl",
-                                        .type                = {EX_FIELD_TYPE_SEQUENCE},
-                                        .nesting             = 1,
-					.cardinality         = {9},
-                                        .component_separator = {'@'}};
-    EXCHECK(ex_put_field_metadata(exoid, field2));
-  }
-
-  {
-    struct ex_field field = (ex_field){.entity_type         = EX_ELEM_BLOCK,
-                                       .entity_id           = blocks[1].id,
-                                       .name                = "User",
-                                       .type                = {EX_FIELD_TYPE_USER_DEFINED},
-                                       .nesting             = 1,
-                                       .cardinality         = {4},
-                                       .component_separator = {'_'}};
-    EXCHECK(ex_put_field_metadata(exoid, field));
-    EXCHECK(ex_put_field_suffices(exoid, field, "h2o,gas,ch4,methane"));
-  }
-
-  { /* Output time steps ... */
-    for (int ts = 0; ts < 1; ts++) {
-      double time_val = (double)(ts + 1) / 100.0;
-
-      EXCHECK(ex_put_time(exoid, ts + 1, &time_val));
-
-      /* write variables */
-      for (int k = 0; k < num_elem_blk; k++) {
-        double *var_vals = (double *)calloc(blocks[k].num_entry, CPU_word_size);
-        for (int var_idx = 0; var_idx < num_block_vars; var_idx++) {
-          for (int elem = 0; elem < blocks[k].num_entry; elem++) {
-            var_vals[elem] = (double)(var_idx + 2) * time_val + elem;
-          }
-          EXCHECK(ex_put_var(exoid, ts + 1, EX_ELEM_BLOCK, var_idx + 1, blocks[k].id,
-                             blocks[k].num_entry, var_vals));
-        }
-        free(var_vals);
-      }
-    }
-  }
-
-  /* close the EXODUS files
-   */
-  EXCHECK(ex_close(exoid));
-  return 0;
-}
diff --git a/packages/seacas/libraries/ioss/cmake/SEACASIoss_config.h.in b/packages/seacas/libraries/ioss/cmake/SEACASIoss_config.h.in
index 15b62c0beaa2..808f36ece452 100644
--- a/packages/seacas/libraries/ioss/cmake/SEACASIoss_config.h.in
+++ b/packages/seacas/libraries/ioss/cmake/SEACASIoss_config.h.in
@@ -11,6 +11,8 @@
 
 #cmakedefine SEACAS_HAVE_EXODUS
 
+#cmakedefine SEACAS_HAVE_EXONULL
+
 #cmakedefine SEACAS_HAVE_CGNS
 
 #cmakedefine SEACAS_HAVE_PAMGEN
diff --git a/packages/seacas/libraries/ioss/src/CMakeLists.txt b/packages/seacas/libraries/ioss/src/CMakeLists.txt
index ee0779d4fdca..3ab10755d3e3 100644
--- a/packages/seacas/libraries/ioss/src/CMakeLists.txt
+++ b/packages/seacas/libraries/ioss/src/CMakeLists.txt
@@ -28,8 +28,12 @@ ENDIF()
 
 IF (${PACKAGE_NAME}_ENABLE_SEACASExodus)
   SET(SEACAS_HAVE_EXODUS ON)
+  IF (ENABLE_ExoNull)
+     SET(SEACAS_HAVE_EXONULL ON)
+  ENDIF()
 ENDIF()
 
+
 TRIBITS_CONFIGURE_FILE(${PACKAGE_NAME}_config.h)
 
 SET(HEADERS "")
@@ -111,9 +115,12 @@ endif()
 
 IF (${PACKAGE_NAME}_ENABLE_SEACASExodus)
   ADD_SUBDIRECTORY(exodus)
-  ADD_SUBDIRECTORY(exonull)
+  IF (ENABLE_ExoNull)
+     ADD_SUBDIRECTORY(exonull)
+  ENDIF()
 ENDIF()
 
+
 IF (TPL_ENABLE_Pamgen OR Trilinos_ENABLE_Pamgen )
   ADD_SUBDIRECTORY(pamgen)
 ENDIF()
diff --git a/packages/seacas/libraries/ioss/src/Ioss_BasisVariableType.C b/packages/seacas/libraries/ioss/src/Ioss_BasisVariableType.C
deleted file mode 100644
index 7515f145e624..000000000000
--- a/packages/seacas/libraries/ioss/src/Ioss_BasisVariableType.C
+++ /dev/null
@@ -1,26 +0,0 @@
-// Copyright(C) 2024 National Technology & Engineering Solutions
-// of Sandia, LLC (NTESS).  Under the terms of Contract DE-NA0003525 with
-// NTESS, the U.S. Government retains certain rights in this software.
-//
-// See packages/seacas/LICENSE for details
-
-#include "Ioss_BasisVariableType.h"
-#include "Ioss_ComposedVariableType.h"
-#include "Ioss_CompositeVariableType.h"
-#include "Ioss_ConstructedVariableType.h"
-#include "Ioss_NamedSuffixVariableType.h"
-#include "Ioss_QuadratureVariableType.h"
-#include "Ioss_Utils.h"
-#include "Ioss_VariableType.h"
-#include <cassert>
-#include <cstdlib>
-#include <cstring>
-#include <fmt/core.h>
-#include <fmt/format.h>
-#include <fmt/ostream.h>
-#include <map>
-#include <sstream>
-#include <string>
-#include <vector>
-
-#include "Ioss_CodeTypes.h"
diff --git a/packages/seacas/libraries/ioss/src/Ioss_ChainGenerator.C b/packages/seacas/libraries/ioss/src/Ioss_ChainGenerator.C
index c2d976f04c92..07c9ca156d0c 100644
--- a/packages/seacas/libraries/ioss/src/Ioss_ChainGenerator.C
+++ b/packages/seacas/libraries/ioss/src/Ioss_ChainGenerator.C
@@ -86,7 +86,7 @@ namespace {
   void get_line_front(Ioss::SideSet *fs, const Ioss::ElementBlock *block,
                       Ioss::chain_t<INT> &element_chains, front_t<INT> &front)
   {
-    const auto     adj_block_name = block->name();
+    const auto    &adj_block_name = block->name();
     Ioss::NameList blocks;
     fs->block_membership(blocks);
     for (const auto &fs_block : blocks) {
@@ -148,7 +148,7 @@ namespace {
                                   connectivity_t &face_connectivity)
   {
     for (const auto &face : faces) {
-      for (int i = 0; i < face.elementCount_; i++) {
+      for (int i = 0; i < face.element_count(); i++) {
         auto element                     = face.element[i] / 10 - offset;
         auto side                        = face.element[i] % 10; // 0-based side
         face_connectivity[element][side] = &face;
@@ -162,11 +162,11 @@ namespace {
         for (size_t j = 0; j < 6; j++) {
           const auto *face = face_connectivity[i][j];
           assert(face != nullptr);
-          int  k       = (face->elementCount_ > 1 && face->element[0] / 10 - offset != i) ? 1 : 0;
+          int  k       = (face->element_count() > 1 && face->element[0] / 10 - offset != i) ? 1 : 0;
           auto element = face->element[k] / 10;
           auto side    = face->element[k] % 10;
           assert(side == j);
-          if (face->elementCount_ > 1) {
+          if (face->element_count() > 1) {
             fmt::print(
                 "[{:3}] Element {}, Side {}/{} is Face {}.\tAdjacent to Element {}, Side {}.\n",
                 l++, element, side, j, face->hashId_, face->element[1 - k] / 10,
@@ -193,8 +193,10 @@ namespace Ioss {
   Ioss::chain_t<INT> generate_element_chains(Ioss::Region &region, const std::string &surface_list,
                                              int debug_level, INT /*dummy*/)
   {
-    debug                    = debug_level;
-    size_t             numel = region.get_property("element_count").get_int();
+    region.get_database()->progress(__func__);
+
+    debug        = debug_level;
+    size_t numel = region.get_property("element_count").get_int();
 
     // Determine which element block(s) are adjacent to the faceset specifying "lines"
     // The `adjacent_blocks` contains the names of all element blocks that are adjacent to the
@@ -223,6 +225,7 @@ namespace Ioss {
     // Generate the faces for use later... (only generate on the blocks touching the front)
     Ioss::FaceGenerator face_generator(region);
     face_generator.generate_block_faces(adjacent_blocks, (INT)0, true);
+    region.get_database()->progress("\tAfter generate_block_faces");
 
     Ioss::chain_t<INT> element_chains(numel);
     for (const auto *block : adjacent_blocks) {
@@ -258,7 +261,7 @@ namespace Ioss {
           assert(opp_side >= 0);
           auto *opp_face = face_connectivity[element - offset][opp_side];
           // See if there is an element attached to the `opp_side`
-          if (opp_face->elementCount_ > 1) {
+          if (opp_face->element_count() > 1) {
             // Determine which is current element and which is adjacent element...
             int  index       = (opp_face->element[0] / 10 ==
                          static_cast<typename decltype(opp_face->element)::value_type>(element))
@@ -296,6 +299,7 @@ namespace Ioss {
         next_front.clear();
       }
     } // End of block loop
+    region.get_database()->progress("\tAfter generating chains");
     return element_chains;
   }
 } // namespace Ioss
diff --git a/packages/seacas/libraries/ioss/src/Ioss_CodeTypes.h b/packages/seacas/libraries/ioss/src/Ioss_CodeTypes.h
index f799bad41fbd..a88d7816b5d6 100644
--- a/packages/seacas/libraries/ioss/src/Ioss_CodeTypes.h
+++ b/packages/seacas/libraries/ioss/src/Ioss_CodeTypes.h
@@ -35,6 +35,7 @@ inline std::string IOSS_SYM_TENSOR() { return {"sym_tensor_33"}; }
 /* #undef IOSS_THREADSAFE */
 /* #undef SEACAS_HAVE_KOKKOS */
 #define SEACAS_HAVE_EXODUS
+#define SEACAS_HAVE_EXONULL
 #define SEACAS_HAVE_CGNS
 /* #undef SEACAS_HAVE_FAODEL */
 #define SEACAS_HAVE_PAMGEN
diff --git a/packages/seacas/libraries/ioss/src/Ioss_Compare.C b/packages/seacas/libraries/ioss/src/Ioss_Compare.C
index 9d99ecb35d42..440622159d29 100644
--- a/packages/seacas/libraries/ioss/src/Ioss_Compare.C
+++ b/packages/seacas/libraries/ioss/src/Ioss_Compare.C
@@ -959,6 +959,11 @@ namespace {
         // the filenames match.
         continue;
       }
+      if (property == "base_filename") {
+        // IGNORE the base_filename.  This is generally the base portion of the filename; we don't
+        // care whether the filenames match.
+        continue;
+      }
 
       // ALLOW the regions to have different names (when copying between databases, io_shell
       // will create "region_1" (input) and "region_2" (output))
diff --git a/packages/seacas/libraries/ioss/src/Ioss_CopyDatabase.C b/packages/seacas/libraries/ioss/src/Ioss_CopyDatabase.C
index a1862313b702..e9f61a7e1268 100644
--- a/packages/seacas/libraries/ioss/src/Ioss_CopyDatabase.C
+++ b/packages/seacas/libraries/ioss/src/Ioss_CopyDatabase.C
@@ -417,7 +417,7 @@ namespace {
       // Get vector of all boundary faces which will be output as the skin...
       const auto &faces = face_generator.faces("ALL");
       for (const auto &face : faces) {
-        if (face.elementCount_ == 1) {
+        if (face.element_count() == 1) {
           boundary.push_back(face);
         }
       }
diff --git a/packages/seacas/libraries/ioss/src/Ioss_DatabaseIO.C b/packages/seacas/libraries/ioss/src/Ioss_DatabaseIO.C
index bee5f80d1d0d..f16b426753cd 100644
--- a/packages/seacas/libraries/ioss/src/Ioss_DatabaseIO.C
+++ b/packages/seacas/libraries/ioss/src/Ioss_DatabaseIO.C
@@ -379,6 +379,8 @@ namespace Ioss {
 
   DatabaseIO::~DatabaseIO() = default;
 
+  Ioss::DataSize DatabaseIO::int_byte_size_data_size() const { return dbIntSizeAPI; }
+
   int DatabaseIO::int_byte_size_api() const
   {
     if (dbIntSizeAPI == USE_INT32_API) {
@@ -1633,7 +1635,7 @@ namespace {
       else {
         char sep = (util.parallel_size() > 1) ? ':' : ' ';
         for (auto &p_time : all_times) {
-          fmt::print(strm, "{:8d}{}", p_time, sep);
+          fmt::print(strm, "{:8}{}", p_time, sep);
         }
       }
       if (util.parallel_size() > 1) {
diff --git a/packages/seacas/libraries/ioss/src/Ioss_DatabaseIO.h b/packages/seacas/libraries/ioss/src/Ioss_DatabaseIO.h
index f5edcdb3b45d..44db7cfe0778 100644
--- a/packages/seacas/libraries/ioss/src/Ioss_DatabaseIO.h
+++ b/packages/seacas/libraries/ioss/src/Ioss_DatabaseIO.h
@@ -279,6 +279,30 @@ namespace Ioss {
       return create_subgroup_nl(group_name);
     }
 
+    bool open_root_group()
+    {
+      IOSS_FUNC_ENTER(m_);
+      return open_root_group_nl();
+    }
+
+    int num_child_group()
+    {
+      IOSS_FUNC_ENTER(m_);
+      return num_child_group_nl();
+    }
+
+    bool open_child_group(int index)
+    {
+      IOSS_FUNC_ENTER(m_);
+      return open_child_group_nl(index);
+    }
+
+    Ioss::NameList groups_describe(bool return_full_names = false)
+    {
+      IOSS_FUNC_ENTER(m_);
+      return groups_describe_nl(return_full_names);
+    }
+
     /** \brief Set the database to the given State.
      *
      *  All transitions must begin from the 'STATE_CLOSED' state or be to
@@ -502,6 +526,7 @@ namespace Ioss {
     IOSS_NODISCARD virtual int int_byte_size_db() const = 0; //! Returns 4 or 8
     IOSS_NODISCARD int         int_byte_size_api() const;    //! Returns 4 or 8
     virtual void               set_int_byte_size_api(Ioss::DataSize size) const;
+    IOSS_NODISCARD Ioss::DataSize int_byte_size_data_size() const;
 
     /*!
      * The owning region of this database.
@@ -737,6 +762,14 @@ namespace Ioss {
     virtual void closeDatabase_nl() const;
     virtual void flush_database_nl() const {}
 
+    virtual void release_memory_nl()
+    {
+      nodeMap.release_memory();
+      edgeMap.release_memory();
+      faceMap.release_memory();
+      elemMap.release_memory();
+    }
+
   private:
     virtual bool ok_nl(bool /* write_message */, std::string * /* error_message */,
                        int *bad_count) const
@@ -757,16 +790,15 @@ namespace Ioss {
       return elemMap.global_to_local(global);
     }
 
-    virtual void release_memory_nl()
-    {
-      nodeMap.release_memory();
-      edgeMap.release_memory();
-      faceMap.release_memory();
-      elemMap.release_memory();
-    }
-
+    virtual int  num_child_group_nl() { return 0; }
+    virtual bool open_child_group_nl(int /* index */) { return false; }
+    virtual bool open_root_group_nl() { return false; }
     virtual bool open_group_nl(const std::string & /* group_name */) { return false; }
     virtual bool create_subgroup_nl(const std::string & /* group_name */) { return false; }
+    virtual Ioss::NameList groups_describe_nl(bool /* return_full_names */)
+    {
+      return Ioss::NameList();
+    }
 
     virtual bool begin_nl(Ioss::State state) = 0;
     virtual bool end_nl(Ioss::State state)   = 0;
diff --git a/packages/seacas/libraries/ioss/src/Ioss_Decomposition.C b/packages/seacas/libraries/ioss/src/Ioss_Decomposition.C
index 1deac79a93d2..5d41b9069e28 100644
--- a/packages/seacas/libraries/ioss/src/Ioss_Decomposition.C
+++ b/packages/seacas/libraries/ioss/src/Ioss_Decomposition.C
@@ -15,6 +15,7 @@
 #include <algorithm>
 #include <cassert>
 #include <fmt/ostream.h>
+#include <fmt/ranges.h>
 #include <numeric>
 
 #if !defined(NO_ZOLTAN_SUPPORT)
@@ -427,9 +428,9 @@ namespace Ioss {
                  m_method, fmt::group_digits(m_globalElementCount), m_processorCount);
 
       if (!m_decompExtra.empty()) {
-	fmt::print(Ioss::OUTPUT(), "\tDecomposition extra data: '{}'.\n", m_decompExtra);
+        fmt::print(Ioss::OUTPUT(), "\tDecomposition extra data: '{}'.\n", m_decompExtra);
       }
-      
+
       if ((size_t)m_processorCount > m_globalElementCount) {
         fmt::print(Ioss::WarnOut(),
                    "Decomposing {} elements across {} mpi ranks will "
diff --git a/packages/seacas/libraries/ioss/src/Ioss_DecompositionUtils.C b/packages/seacas/libraries/ioss/src/Ioss_DecompositionUtils.C
index bec6473e015c..d6d5fdd097b4 100644
--- a/packages/seacas/libraries/ioss/src/Ioss_DecompositionUtils.C
+++ b/packages/seacas/libraries/ioss/src/Ioss_DecompositionUtils.C
@@ -337,9 +337,9 @@ namespace Ioss {
   }
 
   template <typename INT>
-  int DecompUtils::line_decompose(Region &region, size_t num_ranks, const std::string &method,
-                                  const std::string &surface_list,
-                                  std::vector<int> &element_to_proc, INT dummy)
+  void DecompUtils::line_decompose(Region &region, size_t num_ranks, const std::string &method,
+                                   const std::string &surface_list,
+                                   std::vector<int> &element_to_proc, INT dummy)
   {
 
     Ioss::chain_t<INT> element_chains =
@@ -359,20 +359,18 @@ namespace Ioss {
 
     // Make sure all elements on a chain are on the same processor rank...
     line_decomp_modify(element_chains, element_to_proc, num_ranks);
-
-    return 1;
   }
 
-  template IOSS_EXPORT int DecompUtils::line_decompose(Region &region, size_t num_ranks,
-                                                       const std::string &method,
-                                                       const std::string &surface_list,
-                                                       std::vector<int>  &element_to_proc,
-                                                       int                dummy);
-  template IOSS_EXPORT int DecompUtils::line_decompose(Region &region, size_t num_ranks,
-                                                       const std::string &method,
-                                                       const std::string &surface_list,
-                                                       std::vector<int>  &element_to_proc,
-                                                       int64_t            dummy);
+  template IOSS_EXPORT void DecompUtils::line_decompose(Region &region, size_t num_ranks,
+                                                        const std::string &method,
+                                                        const std::string &surface_list,
+                                                        std::vector<int>  &element_to_proc,
+                                                        int                dummy);
+  template IOSS_EXPORT void DecompUtils::line_decompose(Region &region, size_t num_ranks,
+                                                        const std::string &method,
+                                                        const std::string &surface_list,
+                                                        std::vector<int>  &element_to_proc,
+                                                        int64_t            dummy);
 
   template <typename INT>
   std::vector<float> DecompUtils::line_decomp_weights(const Ioss::chain_t<INT> &element_chains,
@@ -466,7 +464,7 @@ namespace Ioss {
                                   std::vector<int> &elem_to_proc, int proc_count);
 
   void DecompUtils::output_decomposition_statistics(const std::vector<int> &elem_to_proc,
-                                                    int proc_count)
+                                                    int                     proc_count)
   {
     // Output histogram of elements / rank...
     std::vector<size_t> elem_per_rank(proc_count);
@@ -475,8 +473,8 @@ namespace Ioss {
     }
 
     size_t number_elements = elem_to_proc.size();
-    size_t proc_width = Ioss::Utils::number_width(proc_count, false);
-    size_t work_width = Ioss::Utils::number_width(number_elements, true);
+    size_t proc_width      = Ioss::Utils::number_width(proc_count, false);
+    size_t work_width      = Ioss::Utils::number_width(number_elements, true);
 
     auto   min_work = *std::min_element(elem_per_rank.begin(), elem_per_rank.end());
     auto   max_work = *std::max_element(elem_per_rank.begin(), elem_per_rank.end());
diff --git a/packages/seacas/libraries/ioss/src/Ioss_DecompositionUtils.h b/packages/seacas/libraries/ioss/src/Ioss_DecompositionUtils.h
index 30b1b35a2ca0..728f40f4ed47 100644
--- a/packages/seacas/libraries/ioss/src/Ioss_DecompositionUtils.h
+++ b/packages/seacas/libraries/ioss/src/Ioss_DecompositionUtils.h
@@ -24,16 +24,16 @@ namespace Ioss {
                                    std::vector<int> &element_to_proc, int proc_count);
 
     static void output_decomposition_statistics(const std::vector<int> &element_to_proc,
-                                                int proc_count);
+                                                int                     proc_count);
 
     template <typename INT>
     static std::vector<float> line_decomp_weights(const Ioss::chain_t<INT> &element_chains,
                                                   size_t                    element_count);
 
     template <typename INT>
-    static int line_decompose(Region &region, size_t num_ranks, const std::string &method,
-                              const std::string &surface_list, std::vector<int> &element_to_proc,
-                              INT dummy);
+    static void line_decompose(Region &region, size_t num_ranks, const std::string &method,
+                               const std::string &surface_list, std::vector<int> &element_to_proc,
+                               INT dummy);
 
     template <typename INT>
     static void decompose_zoltan(const Ioss::Region &region, int ranks, const std::string &method,
diff --git a/packages/seacas/libraries/ioss/src/Ioss_Doxygen.h b/packages/seacas/libraries/ioss/src/Ioss_Doxygen.h
index d3c20468da6a..6206f622dd9a 100644
--- a/packages/seacas/libraries/ioss/src/Ioss_Doxygen.h
+++ b/packages/seacas/libraries/ioss/src/Ioss_Doxygen.h
@@ -198,9 +198,9 @@ file. Then, the first file will be reopened and steps 0.7, 0.8, and
 
  Property              | Value  | Description
 -----------------------|:------:|-----------------------------------------------------------
-MEMORY_READ        | on/[off]   | experimental
-MEMORY_WRITE       | on/[off]   | experimental
-ENABLE_FILE_GROUPS | on/[off]   | experimental
+MEMORY_READ        | on/[off]   | experimental. Read a file into memory at open time, operate on it without disk accesses.
+MEMORY_WRITE       | on/[off]   | experimental. Open and read a file into memory or create and optionally write it back out to disk when nc_close() is called.
+ENABLE_FILE_GROUPS | on/[off]   | experimental.  Opens database in netcdf-4 non-classic mode which is what is required to support groups at netCDF level.
 MINIMAL_NEMESIS_INFO | on/[off] | special case, omit all nemesis data except for nodal communication map
 OMIT_EXODUS_NUM_MAPS | on/[off] | special case, do not output the node and element numbering map.
 EXODUS_CALL_GET_ALL_TIMES| [on] / off | special case -- should the `ex_get_all_times()` function be called.  See below.
diff --git a/packages/seacas/libraries/ioss/src/Ioss_DynamicTopology.C b/packages/seacas/libraries/ioss/src/Ioss_DynamicTopology.C
new file mode 100644
index 000000000000..639f6ba47a59
--- /dev/null
+++ b/packages/seacas/libraries/ioss/src/Ioss_DynamicTopology.C
@@ -0,0 +1,728 @@
+// Copyright(C) 2024 National Technology & Engineering Solutions
+// of Sandia, LLC (NTESS).  Under the terms of Contract DE-NA0003525 with
+// NTESS, the U.S. Government retains certain rights in this software.
+//
+// See packages/seacas/LICENSE for details
+
+#include "Ioss_Assembly.h"
+#include "Ioss_Blob.h"
+#include "Ioss_CodeTypes.h"
+#include "Ioss_CommSet.h"
+#include "Ioss_DBUsage.h"
+#include "Ioss_DatabaseIO.h"
+#include "Ioss_DynamicTopology.h"
+#include "Ioss_EdgeBlock.h"
+#include "Ioss_EdgeSet.h"
+#include "Ioss_ElementBlock.h"
+#include "Ioss_ElementSet.h"
+#include "Ioss_EntityBlock.h"
+#include "Ioss_EntityType.h"
+#include "Ioss_FaceBlock.h"
+#include "Ioss_FaceSet.h"
+#include "Ioss_Field.h"
+#include "Ioss_FileInfo.h"
+#include "Ioss_GroupingEntity.h"
+#include "Ioss_IOFactory.h"
+#include "Ioss_NodeBlock.h"
+#include "Ioss_NodeSet.h"
+#include "Ioss_Region.h"
+#include "Ioss_SideBlock.h"
+#include "Ioss_SideSet.h"
+#include "Ioss_StructuredBlock.h"
+
+#include <climits>
+#include <cstddef>
+#include <fmt/core.h>
+#include <fmt/format.h>
+#include <fmt/ostream.h>
+#include <string>
+
+#include <iostream>
+#include <sstream>
+#include <iomanip>
+#include <assert.h>
+
+#include "Ioss_ParallelUtils.h"
+
+namespace Ioss {
+
+void DynamicTopologyObserver::check_region() const
+{
+  if(nullptr == m_region) {
+    std::ostringstream errmsg;
+    fmt::print(errmsg,
+               "ERROR: A region has not been registered with the "
+               "Dynamic Topology Observer.\n\n");
+    IOSS_ERROR(errmsg);
+  }
+}
+
+void DynamicTopologyObserver::register_region(Region *region)
+{
+  if(nullptr != region && nullptr != m_region && region != m_region) {
+    std::ostringstream errmsg;
+    fmt::print(errmsg,
+               "ERROR: Attempt to re-register different region on "
+               "Dynamic Topology Observer.\n\n");
+    IOSS_ERROR(errmsg);
+  }
+
+  m_region = region;
+}
+
+void DynamicTopologyObserver::register_notifier(DynamicTopologyNotifier *notifier)
+{
+  if(nullptr != notifier && nullptr != m_notifier && notifier != m_notifier) {
+    std::ostringstream errmsg;
+    fmt::print(errmsg,
+               "ERROR: Attempt to re-register different notifier on "
+               "Dynamic Topology Observer.\n\n");
+    IOSS_ERROR(errmsg);
+  }
+
+  m_notifier = notifier;
+}
+
+void DynamicTopologyObserver::set_cumulative_topology_modification(unsigned int type)
+{ m_cumulativeTopologyModification = type; }
+
+unsigned int DynamicTopologyObserver::get_cumulative_topology_modification() const
+{ return m_cumulativeTopologyModification; }
+
+unsigned int DynamicTopologyObserver::get_topology_modification() const
+{ return m_topologyModification; }
+
+void DynamicTopologyObserver::set_topology_modification_nl(unsigned int type)
+{
+  m_topologyModification |= type;
+  m_cumulativeTopologyModification |= type;
+}
+
+void DynamicTopologyObserver::set_topology_modification(unsigned int type)
+{
+  if(!(m_topologyModification & type)) {
+    set_topology_modification_nl(type);
+
+    if(nullptr != m_notifier) {
+      for(auto observer : m_notifier->get_observers()) {
+        observer->set_topology_modification_nl(type);
+      }
+    }
+  }
+}
+
+void DynamicTopologyObserver::reset_topology_modification()
+{
+  m_topologyModification = TOPOLOGY_SAME;
+}
+
+void DynamicTopologyObserver::reset_topology_modification_all()
+{
+  if(m_topologyModification != TOPOLOGY_SAME) {
+    reset_topology_modification();
+
+    if(nullptr != m_notifier) {
+      for(auto observer : m_notifier->get_observers()) {
+        observer->reset_topology_modification();
+      }
+    }
+  }
+}
+
+bool DynamicTopologyObserver::is_topology_modified() const
+{ return m_topologyModification != TOPOLOGY_SAME; }
+
+const ParallelUtils &DynamicTopologyObserver::util() const
+{
+  check_region();
+  return m_region->get_database()->util();
+}
+
+void DynamicTopologyObserver::synchronize_topology_modified_flags()
+{
+  check_region();
+  int num_processors = m_region->get_database()->parallel_size();
+  // Synchronize the topology flags between all processors in case
+  // it has not been set consistently.
+  if (num_processors > 1) {
+    static unsigned int buffer[2];
+    buffer[0] = m_cumulativeTopologyModification;
+    buffer[1] = m_topologyModification;
+
+    util().attribute_reduction(2*sizeof(unsigned int), reinterpret_cast<char*>(buffer));
+
+    m_cumulativeTopologyModification = buffer[0];
+    m_topologyModification = buffer[1];
+  }
+}
+
+int DynamicTopologyObserver::get_cumulative_topology_modification_field()
+{
+  check_region();
+  const std::string variable_name = topology_modification_change_name();
+
+  int ivalue = 0;
+
+  if (m_region->field_exists(variable_name)) {
+    Field topo_field = m_region->get_field(variable_name);
+    if (topo_field.get_type() == Field::INTEGER) {
+      m_region->get_field_data(variable_name, &ivalue, sizeof(int));
+    } else {
+      double value;
+      m_region->get_field_data(variable_name, &value, sizeof(double));
+      ivalue = (int)value;
+    }
+  }
+
+  int num_processors = m_region->get_database()->parallel_size();
+  // Synchronize the value between all processors in case
+  // it has not been set consistently.
+  if (num_processors > 1) {
+    unsigned int buffer[1];
+    buffer[0] = ivalue;
+
+    util().attribute_reduction(sizeof(unsigned int), reinterpret_cast<char*>(buffer));
+
+    ivalue = (int)buffer[0];
+  }
+
+  m_cumulativeTopologyModification = ivalue;
+
+  return ivalue;
+}
+
+void DynamicTopologyObserver::define_model()
+{
+
+}
+
+void DynamicTopologyObserver::write_model()
+{
+
+}
+
+void DynamicTopologyObserver::define_transient()
+{
+
+}
+
+
+DynamicTopologyBroker* DynamicTopologyBroker::broker()
+{
+  static DynamicTopologyBroker broker_;
+  return &broker_;
+}
+
+void DynamicTopologyBroker::register_model(const std::string& model_name)
+{
+  auto iter = m_notifiers.find(model_name);
+  if(iter != m_notifiers.end()) {
+    return;
+  }
+
+  m_notifiers[model_name] = std::make_shared<DynamicTopologyNotifier>(model_name);
+}
+
+std::shared_ptr<DynamicTopologyNotifier> DynamicTopologyBroker::get_notifier(const std::string& model_name) const
+{
+  auto iter = m_notifiers.find(model_name);
+  if(iter != m_notifiers.end()) {
+    return iter->second;
+  }
+
+  return {};
+}
+
+std::vector<std::shared_ptr<DynamicTopologyObserver>> DynamicTopologyBroker::get_observers(const std::string& model_name) const
+{
+  std::vector<std::shared_ptr<DynamicTopologyObserver>> observers;
+
+  auto notifier = get_notifier(model_name);
+
+  if(notifier) {
+    return notifier->get_observers();
+  }
+
+  return observers;
+}
+
+void DynamicTopologyBroker::remove_model(const std::string& model_name)
+{
+  auto iter = m_notifiers.find(model_name);
+  if(iter != m_notifiers.end()) {
+    m_notifiers.erase(iter);
+  }
+}
+
+void DynamicTopologyBroker::clear_models()
+{
+  m_notifiers.clear();
+}
+
+void DynamicTopologyBroker::register_observer(const std::string& model_name,
+                                              std::shared_ptr<DynamicTopologyObserver> observer)
+{
+  auto notifier = get_notifier(model_name);
+
+  if(!notifier) {
+    register_model(model_name);
+    notifier = get_notifier(model_name);
+  }
+
+  notifier->register_observer(observer);
+}
+
+void DynamicTopologyBroker::register_observer(const std::string& model_name,
+                                              std::shared_ptr<DynamicTopologyObserver> observer,
+                                              Region& region)
+{
+  region.register_mesh_modification_observer(observer);
+  register_observer(model_name, observer);
+}
+
+void DynamicTopologyBroker::reset_topology_modification(const std::string& model_name)
+{
+  auto notifier = get_notifier(model_name);
+
+  if(!notifier) return;
+
+  notifier->reset_topology_modification();
+}
+
+void DynamicTopologyBroker::set_topology_modification(const std::string& model_name, unsigned int type)
+{
+  auto notifier = get_notifier(model_name);
+
+  if(!notifier) return;
+
+  notifier->set_topology_modification(type);
+}
+
+
+struct DynamicTopologyObserverCompare {
+  bool operator()(const std::shared_ptr<DynamicTopologyObserver> & lhs,
+                  const std::shared_ptr<DynamicTopologyObserver> & rhs) const {
+    assert(lhs && (lhs->get_region() != nullptr));
+    assert(rhs && (rhs->get_region() != nullptr));
+    return (lhs->get_region() < rhs->get_region());
+  }
+};
+
+void DynamicTopologyNotifier::register_observer(std::shared_ptr<DynamicTopologyObserver> observer)
+{
+  observer->register_notifier(this);
+  m_observers.push_back(observer);
+  std::sort(m_observers.begin(), m_observers.end(), DynamicTopologyObserverCompare());
+}
+
+void DynamicTopologyNotifier::unregister_observer(std::shared_ptr<DynamicTopologyObserver> observer)
+{
+  auto iter = std::find(m_observers.begin(), m_observers.end(), observer);
+  if (iter != m_observers.end()) {
+    (*iter)->register_notifier(nullptr);
+    m_observers.erase(iter);
+  }
+}
+
+void DynamicTopologyNotifier::reset_topology_modification()
+{
+  for(std::shared_ptr<DynamicTopologyObserver>& observer : m_observers) {
+    observer->reset_topology_modification();
+  }
+}
+
+void DynamicTopologyNotifier::set_topology_modification(unsigned int type)
+{
+  for(std::shared_ptr<DynamicTopologyObserver>& observer : m_observers) {
+    observer->set_topology_modification(type);
+  }
+}
+
+
+DynamicTopologyFileControl::DynamicTopologyFileControl(Region *region, unsigned int fileCyclicCount,
+                                                       IfDatabaseExistsBehavior &ifDatabaseExists,
+                                                       unsigned int &dbChangeCount)
+  : m_region(region)
+  , m_fileCyclicCount(fileCyclicCount)
+  , m_ifDatabaseExists(ifDatabaseExists)
+  , m_dbChangeCount(dbChangeCount)
+{
+  if(nullptr == region) {
+    std::ostringstream errmsg;
+    fmt::print(errmsg, "ERROR: null region passed in as argument to DynamicTopologyFileControl");
+    IOSS_ERROR(errmsg);
+  }
+
+  m_ioDB   = region->get_property("base_filename").get_string();
+  m_dbType = region->get_property("database_type").get_string();
+}
+
+const ParallelUtils &DynamicTopologyFileControl::util() const
+{
+  return m_region->get_database()->util();
+}
+
+bool DynamicTopologyFileControl::file_exists(const std::string &filename,
+                                             const std::string &db_type,
+                                             Ioss::DatabaseUsage db_usage)
+{
+  bool exists = false;
+  int par_size = m_region->get_database()->parallel_size();
+  int par_rank = m_region->get_database()->parallel_rank();
+  bool is_parallel = par_size > 1;
+  std::string full_filename = filename;
+  if (is_parallel && db_type == "exodusII" && db_usage != Ioss::WRITE_HISTORY) {
+    full_filename = Ioss::Utils::decode_filename(filename, par_rank, par_size);
+  }
+
+  if (!is_parallel || par_rank == 0) {
+    // Now, see if this file exists...
+    // Don't want to do a system call on all processors since it can take minutes
+    // on some of the larger machines, filesystems, and processor counts...
+    Ioss::FileInfo file = Ioss::FileInfo(full_filename);
+    exists = file.exists();
+  }
+
+  if (is_parallel) {
+    int iexists = exists ? 1 : 0;
+    util().broadcast(iexists, 0);
+    exists = iexists == 1;
+  }
+  return exists;
+}
+
+std::string DynamicTopologyFileControl::get_unique_filename(Ioss::DatabaseUsage db_usage)
+{
+  std::string filename = m_ioDB;
+
+  do {
+    // Run this loop at least once for all files.  If this is an automatic
+    // restart, then make sure that the generated file does not already exist,
+    // so keep running the loop until we generate a filename that doesn't exist...
+    std::ostringstream tmp_filename;
+    tmp_filename << m_ioDB;
+
+    // Don't append the "-s000X" the first time in case the base filename doesn't
+    // exist -- we want write to the name specified by the user if at all possible and
+    // once that exists, then start adding on the suffix...
+    if (m_dbChangeCount > 1) {
+      tmp_filename << "-s" << std::setw(4) << std::setfill('0') << m_dbChangeCount;
+    }
+    filename = tmp_filename.str();
+    ++m_dbChangeCount;
+  } while(file_exists(filename, m_dbType, db_usage));
+  --m_dbChangeCount;
+  return filename;
+}
+
+std::string DynamicTopologyFileControl::construct_database_filename(int& step, Ioss::DatabaseUsage db_usage)
+{
+  // Filename will be of the form -- ioDB-sxxxx where xxxx is step
+  // number.  Assume maximum of 9999 steps (will do more, but won't have
+  // good lineup of step numbers.
+  // Check database for validity (filename and a type)
+  if(m_ioDB.empty() || m_dbType.empty())
+  {
+    std::string error_message;
+    if(m_dbType.empty())
+      error_message += "The database TYPE has not been defined\n";
+
+    if(m_ioDB.empty())
+    {
+      error_message += "The database FILENAME has not been defined\n";
+    }
+    std::ostringstream errmsg;
+    fmt::print(errmsg, error_message);
+    IOSS_ERROR(errmsg);
+  }
+  assert(!m_ioDB.empty());
+  assert(!m_dbType.empty());
+  std::string filename = m_ioDB;
+  if(m_fileCyclicCount > 0)
+  {
+    // In this mode, we close the old file and open a new file
+    // every time this is called. The file suffix cycles through
+    // the first fileCyclicCount'th entries in A,B,C,D,E,F,...
+    if(step == 0)
+      step++;
+
+    static std::string suffix = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
+    std::string tmp = "-" + suffix.substr((step - 1) % m_fileCyclicCount, 1);
+    filename += tmp;
+    m_properties.add(Ioss::Property("APPEND_OUTPUT", Ioss::DB_OVERWRITE));
+  }
+  else
+  {
+    if(m_region->model_is_written())
+    {
+      // After the initial open, we want to add suffix if the topology changes
+      // during the run
+      m_ifDatabaseExists = Ioss::DB_ADD_SUFFIX_OVERWRITE;
+    }
+
+    // Handle complications of DB_APPEND mode...
+    // If in DB_APPEND mode, then we don't output metadata
+    // information, so some knowledge is needed at this level if
+    // we are appending.  If user specified APPEND, but the file
+    // doesn't yet exist OR it does exist and we are not
+    // restarting, change the mode to OVERWRITE.
+    // 0. Must be restarting; either manual or automatic.
+    std::shared_ptr<DynamicTopologyObserver> observer = m_region->get_mesh_modification_observer();
+
+    if(m_ifDatabaseExists == Ioss::DB_APPEND)
+    {
+      if(!observer->is_restart_requested())
+      {
+        // Not restarting
+        m_ifDatabaseExists = Ioss::DB_OVERWRITE;
+      }
+      else if(!file_exists(m_ioDB, m_dbType, db_usage))
+      {
+        m_ifDatabaseExists = Ioss::DB_OVERWRITE;
+      }
+    }
+    if(step > 1 || (m_dbChangeCount > 1))
+    {
+      // Use the !is_input_event test since restart input files already have the
+      // -s000x extension...
+      if(m_ifDatabaseExists == Ioss::DB_APPEND)
+      {
+        std::ostringstream tmp_filename;
+        tmp_filename << m_ioDB;
+        filename = m_ioDB;
+        if(m_dbChangeCount > 1)
+        {
+          tmp_filename << "-s" << std::setw(4) << std::setfill('0') << m_dbChangeCount;
+        }
+        size_t inc = 0;
+        while(file_exists(tmp_filename.str(), m_dbType, db_usage))
+        {
+          filename = tmp_filename.str();
+          tmp_filename.clear();
+          tmp_filename.str("");
+          tmp_filename << m_ioDB << "-s" << std::setw(4) << std::setfill('0') << m_dbChangeCount + (++inc);
+        }
+        if(inc > 0)
+        {
+          m_dbChangeCount += (inc - 1);
+        }
+        else
+        {
+          m_ifDatabaseExists = Ioss::DB_OVERWRITE;
+        }
+      }
+      else if(m_ifDatabaseExists == Ioss::DB_ADD_SUFFIX)
+      {
+        filename = get_unique_filename(db_usage);
+      }
+      else if(m_ifDatabaseExists == Ioss::DB_ADD_SUFFIX_OVERWRITE)
+      {
+        if(m_dbChangeCount > 0)
+        {
+          std::ostringstream tmp_filename;
+          tmp_filename << m_ioDB << "-s" << std::setw(4) << std::setfill('0') << ++m_dbChangeCount;
+          filename = tmp_filename.str();
+        }
+        else
+        {
+          filename = m_ioDB;
+        }
+      }
+      else
+      {
+        filename = m_ioDB;
+      }
+    }
+    else if(m_ifDatabaseExists == Ioss::DB_ADD_SUFFIX)
+    {
+      filename = get_unique_filename(db_usage);
+    }
+    else
+    {
+      filename = m_ioDB;
+    }
+
+    m_properties.add(Ioss::Property("APPEND_OUTPUT", m_ifDatabaseExists));
+    // A little complicated on deciding whether we are actually
+    // overwriting the database.  The 'validate' routine for Results and
+    // History will call create_database once the parser block is
+    // ended. This routine will then create the database and the
+    // ioRegion_. However, the database will not really be opened or
+    // written to at this time.  If the code is auto-restarting, then it will
+    // detect that the database exists and create a database with the
+    // -s000x extension.
+    // At this point, we need to skip the 'abort_if_exists' test if we
+    // are in this routine from the 'validate' and we are restarting
+    // since we won't really write to the file.  So, the cases where we
+    // *don't* check are:
+    // -- is_input_event(db_usage)
+    // -- ifExists_ == DB_OVERWRITE || DB_ADD_SUFFIX_OVERWRITE || DB_APPEND
+    // -- is_automatic_restart() && step == 0 (coming from validate)
+    if(m_ifDatabaseExists != DB_OVERWRITE &&
+       m_ifDatabaseExists != DB_APPEND &&
+       m_ifDatabaseExists != DB_ADD_SUFFIX_OVERWRITE &&
+       !(step == 0 && observer->is_automatic_restart()))
+    {
+      abort_if_exists(filename, m_dbType, db_usage);
+    }
+  }
+  return filename;
+}
+
+bool DynamicTopologyFileControl::abort_if_exists(const std::string &filename,
+                                                 const std::string &db_type,
+                                                 Ioss::DatabaseUsage db_usage)
+{
+  // Check whether file with same name as database already exists.  If so,
+  // print error message and stop...
+  // At the current time, only check on processor 0 and assume if it doesn't exist
+  // there, then it doesn't exist on other processors.  Or, if it doesn't exist on
+  // processor 0, then it doesn't matter if it doesn't exist on other processors
+  // since we don't have all pieces...
+
+  bool exists = file_exists(filename, db_type, db_usage);
+  if (exists) {
+    std::ostringstream errmsg;
+    fmt::print(errmsg,
+               "ERROR: The database file named '{} exists"
+               "and would be overwritten if the code continued.\n\n"
+               "Input options specified that this file *not* be overwritten,\n"
+               "\tso you must rename or remove this file and restart the code.\n",
+               filename);
+    IOSS_ERROR(errmsg);
+  }
+  return exists;
+}
+
+Ioss::DatabaseIO * DynamicTopologyFileControl::clone_output_database(int steps)
+{
+  auto current_db = m_region->get_database();
+
+  if (current_db->is_input())
+    return nullptr;
+
+  const Ioss::PropertyManager& current_properties = current_db->get_property_manager();
+  Ioss::NameList names;
+  current_properties.describe(&names);
+
+  // Iterate through properties and transfer to new output database...
+  Ioss::NameList::const_iterator I;
+  for (I = names.begin(); I != names.end(); ++I) {
+    if (!current_properties.exists(*I))
+      m_properties.add(current_properties.get(*I));
+  }
+
+  auto db_usage = current_db->usage();
+
+  std::string filename = construct_database_filename(steps, db_usage);
+
+  Ioss::DatabaseIO *db = Ioss::IOFactory::create(m_dbType, filename, db_usage,
+                                                 current_db->util().communicator(),
+                                                 m_properties);
+
+  if (nullptr == db) {
+    std::ostringstream errmsg;
+    fmt::print(errmsg,
+               "ERROR: unable to create output database named '{}'"
+               " of type '{}'", filename, m_dbType);
+    IOSS_ERROR(errmsg);
+  }
+
+  assert(db != nullptr);
+  if(!db->ok(true)) {
+    std::ostringstream errmsg;
+    fmt::print(errmsg,
+               "ERROR: unable to validate output database named '{}'"
+               " of type '{}'", filename, m_dbType);
+    IOSS_ERROR(errmsg);
+  }
+
+  db->set_field_separator(current_db->get_field_separator());
+  db->set_surface_split_type(current_db->get_surface_split_type());
+  db->set_maximum_symbol_length(current_db->maximum_symbol_length());
+  db->set_int_byte_size_api(current_db->int_byte_size_data_size());
+
+  return db;
+}
+
+template<typename T>
+void update_database_for_grouping_entities(const T& container, Ioss::DatabaseIO *db)
+{
+  for(auto * entity : container) {
+    Ioss::GroupingEntity* ge = dynamic_cast<Ioss::GroupingEntity*>(entity);
+    assert(ge != nullptr);
+
+    if(ge->type() == Ioss::SIDESET) {
+      Ioss::SideSet *sset = dynamic_cast<Ioss::SideSet*>(ge);
+      assert(sset != nullptr);
+
+      sset->reset_database(db);
+      const auto &sblocks = sset->get_side_blocks();
+      for (const auto &sblock : sblocks) {
+        sblock->reset_database(db);
+      }
+    } else {
+      ge->reset_database(db);
+    }
+  }
+}
+
+bool DynamicTopologyFileControl::replace_output_database(Ioss::DatabaseIO *db)
+{
+  auto current_db = m_region->get_database();
+
+  if (current_db->is_input())
+    return false;
+
+  current_db->finalize_database();
+  current_db->closeDatabase();
+  delete current_db;
+
+  m_region->reset_database(db);
+  db->set_region(m_region);
+
+  update_database_for_grouping_entities(m_region->get_node_blocks(), db);
+  update_database_for_grouping_entities(m_region->get_edge_blocks(), db);
+  update_database_for_grouping_entities(m_region->get_face_blocks(), db);
+  update_database_for_grouping_entities(m_region->get_element_blocks(), db);
+  update_database_for_grouping_entities(m_region->get_sidesets(), db);
+  update_database_for_grouping_entities(m_region->get_nodesets(), db);
+  update_database_for_grouping_entities(m_region->get_edgesets(), db);
+  update_database_for_grouping_entities(m_region->get_facesets(), db);
+  update_database_for_grouping_entities(m_region->get_elementsets(), db);
+  update_database_for_grouping_entities(m_region->get_commsets(), db);
+  update_database_for_grouping_entities(m_region->get_structured_blocks(), db);
+  update_database_for_grouping_entities(m_region->get_assemblies(), db);
+  update_database_for_grouping_entities(m_region->get_blobs(), db);
+
+  return true;
+}
+
+void DynamicTopologyFileControl::clone_and_replace_output_database(int steps)
+{
+  auto db = clone_output_database(steps);
+
+  if(nullptr != db)
+    replace_output_database(db);
+}
+
+void DynamicTopologyFileControl::add_output_database_group(int steps)
+{
+  auto current_db = m_region->get_database();
+
+  std::ostringstream oss;
+  oss << group_prefix();
+  oss << m_dbChangeCount;
+
+  current_db->release_memory();
+  current_db->open_root_group();
+  current_db->create_subgroup(oss.str());
+
+  m_dbChangeCount++;
+}
+
+}
+
+
+
+
diff --git a/packages/seacas/libraries/ioss/src/Ioss_DynamicTopology.h b/packages/seacas/libraries/ioss/src/Ioss_DynamicTopology.h
new file mode 100644
index 000000000000..76de048fd491
--- /dev/null
+++ b/packages/seacas/libraries/ioss/src/Ioss_DynamicTopology.h
@@ -0,0 +1,238 @@
+// Copyright(C) 2024 National Technology & Engineering Solutions
+// of Sandia, LLC (NTESS).  Under the terms of Contract DE-NA0003525 with
+// NTESS, the U.S. Government retains certain rights in this software.
+//
+// See packages/seacas/LICENSE for details
+
+#pragma once
+
+#include "Ioss_DBUsage.h"
+#include "Ioss_DatabaseIO.h"      // for DatabaseIO
+#include "Ioss_ParallelUtils.h"   // for ParallelUtils
+#include "Ioss_PropertyManager.h" // for PropertyManager
+#include <assert.h>
+#include <cstddef> // for size_t, nullptr
+#include <cstdint> // for int64_t
+
+#include "Ioss_CodeTypes.h"
+#include "Ioss_Utils.h"
+#include "ioss_export.h"
+
+#include <iosfwd> // for ostream
+#include <sstream>
+#include <string>  // for string, operator<
+#include <strings.h>
+
+namespace Ioss {
+  class Region;
+  class DynamicTopologyNotifier;
+
+  /*! The TopologyModified enumeration is used as an argument to the
+   *  topology_modified() functions in io to
+   *  specify the type of topology modification that has occurred.  The
+   *  calls to topology_modified() are cumulative between
+   *  output steps, so a call with TOPOLOGY_REORDER followed by a call
+   *  with TOPOLOGY_SHUFFLE will do the right thing.  Typical examples
+   *  of when these would be used are:
+   *  - TOPOLOGY_SAME: No change, but easier to call function than not.
+   *  - TOPOLOGY_REORDER: Element Death which reorders the Registrars
+   *  - TOPOLOGY_SHUFFLE: Load Balancing
+   *  - TOPOLOGY_HADAPT: H-Adaptivity
+   *  - TOPOLOGY_GHOST: Ghost nodes/edges/faces/elements created/destroyed
+   *  - TOPOLOGY_GEOMETRY: Model data is modified, overlap removal.
+   *  - TOPOLOGY_CREATEDELETE: Surface erosion, particle creation
+   *  - TOPOLOGY_UNKNOWN: Something else, catchall option.
+   */
+  enum TopologyModified {
+    TOPOLOGY_SAME           = (       0), //!< No change, also used for initialization
+    TOPOLOGY_REORDER        = (1U <<  0), //!< Data structures reordered on processor, no change between procs.
+    TOPOLOGY_SHUFFLE        = (1U <<  1), //!< Globally the same, data moved among processors.
+    TOPOLOGY_HADAPT         = (1U <<  2), //!< Elements split/combined; not moved cross-proc
+    TOPOLOGY_GEOMETRY       = (1U <<  3), //!< Geometry (mesh coordinates) modified. Restart needs to know this.
+    TOPOLOGY_CREATEFACE     = (1U <<  4), //!< Face/Edge are created/deleted.
+    TOPOLOGY_CREATEELEM     = (1U <<  5), //!< Elements are created/deleted.
+    TOPOLOGY_CREATENODE     = (1U <<  6), //!< Nodes are created/deleted.
+    TOPOLOGY_CREATEASSEMBLY = (1U <<  7), //!< Assemblies are created/deleted.
+    TOPOLOGY_UNKNOWN        = (1U <<  8), //!< Unknown change, recreate from scratch.
+  };
+
+  enum class FileControlOption { CONTROL_NONE, CONTROL_AUTO_MULTI_FILE, CONTROL_AUTO_GROUP_FILE };
+
+  class IOSS_EXPORT DynamicTopologyObserver
+  {
+  public:
+    DynamicTopologyObserver(Region *region)
+    : m_region(region) {}
+
+    virtual ~DynamicTopologyObserver() {}
+
+    virtual void reset_topology_modification_all();
+    virtual void reset_topology_modification();
+    virtual void set_topology_modification(unsigned int type);
+    virtual unsigned int get_topology_modification() const;
+
+    virtual unsigned int get_cumulative_topology_modification() const;
+    virtual void         set_cumulative_topology_modification(unsigned int type);
+
+    int get_cumulative_topology_modification_field();
+
+    virtual bool is_topology_modified() const;
+    virtual bool is_automatic_restart() const { return false; }
+    virtual bool is_restart_requested() const { return false; }
+
+    static const std::string topology_modification_change_name()
+    {
+      return std::string("CUMULATIVE_TOPOLOGY_MODIFICATION");
+    }
+
+    void    register_region(Region *region);
+    Region *get_region() const { return m_region; }
+
+    void register_notifier(DynamicTopologyNotifier *notifier);
+    DynamicTopologyNotifier* get_notifier() const { return m_notifier; }
+
+    virtual void define_model();
+    virtual void write_model();
+    virtual void define_transient();
+
+    virtual FileControlOption get_control_option() const { return FileControlOption::CONTROL_NONE; }
+
+  protected:
+    Region      *m_region{nullptr};
+    unsigned int m_topologyModification{TOPOLOGY_SAME};
+    unsigned int m_cumulativeTopologyModification{TOPOLOGY_SAME};
+
+    bool m_automaticRestart{false};
+    bool m_restartRequested{false};
+
+    DynamicTopologyNotifier *m_notifier{nullptr};
+
+    void check_region() const;
+    IOSS_NODISCARD const ParallelUtils &util() const;
+    void synchronize_topology_modified_flags();
+
+    void set_topology_modification_nl(unsigned int type);
+
+  private:
+    DynamicTopologyObserver();
+  };
+
+
+  class IOSS_EXPORT DynamicTopologyNotifier
+  {
+  public:
+    DynamicTopologyNotifier(const std::string& model_name)
+    : m_modelName(model_name) {}
+
+    virtual ~DynamicTopologyNotifier() = default;
+
+    std::string name() const { return m_modelName; }
+
+    std::vector<std::shared_ptr<DynamicTopologyObserver>> get_observers() const { return m_observers; }
+
+    void register_observer(std::shared_ptr<DynamicTopologyObserver> observer);
+
+    void unregister_observer(std::shared_ptr<DynamicTopologyObserver> observer);
+
+    void reset_topology_modification();
+
+    void set_topology_modification(unsigned int type);
+
+    template<typename ObserverType>
+    bool has_observer_type() const
+    {
+      bool found = false;
+
+      for(const std::shared_ptr<DynamicTopologyObserver>& observer : m_observers) {
+        if (dynamic_cast<const ObserverType*>(observer.get()) != nullptr) {
+          found = true;
+          break;
+        }
+      }
+      return found;
+    }
+
+    template<typename ObserverType>
+    std::vector<std::shared_ptr<ObserverType>> get_observer_type() const
+    {
+      std::vector<std::shared_ptr<ObserverType>> typed_observers;
+
+      for(const std::shared_ptr<DynamicTopologyObserver> &observer : m_observers) {
+        ObserverType* typed_observer = dynamic_cast<ObserverType*>(observer.get());
+        if (typed_observer != nullptr) {
+          typed_observers.push_back(std::dynamic_pointer_cast<ObserverType>(observer));
+        }
+      }
+
+      return typed_observers;
+    }
+
+  private:
+    const std::string m_modelName;
+    std::vector<std::shared_ptr<DynamicTopologyObserver>> m_observers;
+  };
+
+
+  class IOSS_EXPORT DynamicTopologyBroker
+  {
+  public:
+    static DynamicTopologyBroker *broker();
+
+    void register_model(const std::string& model_name);
+    void remove_model(const std::string& model_name);
+    void clear_models();
+
+    std::shared_ptr<DynamicTopologyNotifier> get_notifier(const std::string& model_name) const;
+    std::vector<std::shared_ptr<DynamicTopologyObserver>> get_observers(const std::string& model_name) const;
+
+    void register_observer(const std::string& model_name, std::shared_ptr<DynamicTopologyObserver> observer);
+    void register_observer(const std::string& model_name, std::shared_ptr<DynamicTopologyObserver> observer, Region& region);
+
+    void reset_topology_modification(const std::string& model_name);
+    void set_topology_modification(const std::string& model_name, unsigned int type);
+
+  private:
+    DynamicTopologyBroker() {};
+    DynamicTopologyBroker(DynamicTopologyBroker&);
+
+    std::map<std::string, std::shared_ptr<DynamicTopologyNotifier>> m_notifiers;
+  };
+
+
+  class IOSS_EXPORT DynamicTopologyFileControl
+  {
+  public:
+    DynamicTopologyFileControl(Region *region, unsigned int fileCyclicCount,
+                               IfDatabaseExistsBehavior &ifDatabaseExists,
+                               unsigned int             &dbChangeCount);
+
+    void clone_and_replace_output_database(int steps = 0);
+    void add_output_database_group(int steps = 0);
+
+    static std::string group_prefix() { return "IOSS_FILE_GROUP-"; }
+
+  private:
+    Region     *m_region{nullptr};
+    std::string m_ioDB;
+    std::string m_dbType;
+
+    PropertyManager m_properties;
+
+    unsigned int              m_fileCyclicCount;
+    IfDatabaseExistsBehavior &m_ifDatabaseExists;
+    unsigned int             &m_dbChangeCount;
+
+    IOSS_NODISCARD const ParallelUtils &util() const;
+
+    std::string get_unique_filename(DatabaseUsage db_usage);
+    std::string construct_database_filename(int &step, DatabaseUsage db_usage);
+    bool        file_exists(const std::string &filename, const std::string &db_type,
+                            DatabaseUsage db_usage);
+    bool        abort_if_exists(const std::string &filename, const std::string &db_type,
+                                DatabaseUsage db_usage);
+
+    DatabaseIO *clone_output_database(int steps);
+    bool        replace_output_database(DatabaseIO *db);
+  };
+
+} // namespace Ioss
diff --git a/packages/seacas/libraries/ioss/src/Ioss_FaceGenerator.C b/packages/seacas/libraries/ioss/src/Ioss_FaceGenerator.C
index 04bd1effabf9..f8bb48abecb2 100644
--- a/packages/seacas/libraries/ioss/src/Ioss_FaceGenerator.C
+++ b/packages/seacas/libraries/ioss/src/Ioss_FaceGenerator.C
@@ -93,8 +93,8 @@ namespace {
         std::array<size_t, 4> conn = {{0, 0, 0, 0}};
         for (int j = 0; j < face_node_count[face]; j++) {
           size_t fnode = offset + face_conn[face][j];
-          size_t lnode = connectivity[fnode]; // local since "connectivity_raw"
-          conn[j]      = local_ids ? lnode : ids[lnode - 1];      // Convert to global
+          size_t lnode = connectivity[fnode];                // local since "connectivity_raw"
+          conn[j]      = local_ids ? lnode : ids[lnode - 1]; // Convert to global
           id += hash_ids[lnode - 1];
         }
         create_face(faces, id, conn, elem_id, face);
@@ -160,7 +160,7 @@ namespace {
       std::vector<INT> potential_count(proc_count);
       std::vector<int> shared_nodes(proc_count);
       for (auto &face : faces) {
-        if (face.elementCount_ == 1) {
+        if (face.element_count() == 1) {
           // On 'boundary' -- try to determine whether on processor or exterior
           // boundary
           int face_node_count = 0;
@@ -193,7 +193,7 @@ namespace {
       std::vector<int64_t> potential_faces(6 * potential);
 
       for (auto &face : faces) {
-        if (face.elementCount_ == 1) {
+        if (face.element_count() == 1) {
           // On 'boundary' -- try to determine whether on processor or exterior
           // boundary
           int face_node_count = 0;
@@ -219,7 +219,7 @@ namespace {
               potential_faces[6 * offset + 3] = face.connectivity_[2];
               potential_faces[6 * offset + 4] = face.connectivity_[3];
               potential_faces[6 * offset + 5] = face.element[0];
-              assert(face.elementCount_ == 1);
+              assert(face.element_count() == 1);
               potential_offset[i]++;
             }
             shared_nodes[i] = 0; // Reset for next trip through face.connectivity_ loop
@@ -326,13 +326,18 @@ namespace Ioss {
 
   FaceUnorderedSet &FaceGenerator::faces(const Ioss::ElementBlock *block)
   {
-    auto name = block->name();
+    const auto &name = block->name();
     return faces_[name];
   }
 
+  void FaceGenerator::progress(const std::string &output) const
+  {
+    region_.get_database()->progress(output);
+  }
+
   void FaceGenerator::clear(const Ioss::ElementBlock *block)
   {
-    auto name = block->name();
+    const auto &name = block->name();
     faces_[name].clear();
   }
 
@@ -342,6 +347,7 @@ namespace Ioss {
   template <typename INT>
   void FaceGenerator::generate_faces(INT /*dummy*/, bool block_by_block, bool local_ids)
   {
+    progress(__func__);
     if (block_by_block) {
       const auto &ebs = region_.get_element_blocks();
       generate_block_faces(ebs, INT(0), local_ids);
@@ -353,6 +359,7 @@ namespace Ioss {
 
   template <typename INT> void FaceGenerator::hash_node_ids(const std::vector<INT> &node_ids)
   {
+    progress(__func__);
     hashIds_.reserve(node_ids.size());
     for (auto &id : node_ids) {
       hashIds_.push_back(id_hash(id));
@@ -376,11 +383,12 @@ namespace Ioss {
   void FaceGenerator::generate_block_faces(const Ioss::ElementBlockContainer &ebs, INT /*dummy*/,
                                            bool                               local_ids)
   {
+    progress(__func__);
     // Convert ids into hashed-ids
     Ioss::NodeBlock *nb = region_.get_node_blocks()[0];
 
 #if DO_TIMING
-      auto starth = std::chrono::steady_clock::now();
+    auto starth = std::chrono::steady_clock::now();
 #endif
     std::vector<INT> ids;
     if (local_ids) {
@@ -391,10 +399,11 @@ namespace Ioss {
       hash_node_ids(ids);
     }
 #if DO_TIMING
-      auto endh = std::chrono::steady_clock::now();
+    auto endh = std::chrono::steady_clock::now();
 #endif
 
     for (const auto &eb : ebs) {
+      progress("\tgenerate_block_faces: " + eb->name());
       const std::string &name    = eb->name();
       size_t             numel   = eb->entity_count();
       size_t             reserve = 2.0 * numel;
@@ -402,6 +411,7 @@ namespace Ioss {
       faces_[name].max_load_factor(0.9);
       internal_generate_faces(eb, faces_[name], ids, hashIds_, local_ids, (INT)0);
     }
+    progress("\tgenerate_block_faces: end of blocks");
 
 #if DO_TIMING
     auto endf = std::chrono::steady_clock::now();
@@ -437,11 +447,13 @@ namespace Ioss {
     fmt::print("Total time:          \t{:.6} ms\n\n",
                std::chrono::duration<double, std::milli>(endp - starth).count());
 #endif
+    progress("\tgenerate_block_faces: end of routine");
     hashIds_.clear();
   }
 
   template <typename INT> void FaceGenerator::generate_model_faces(INT /*dummy*/, bool local_ids)
   {
+    progress(__func__);
     // Convert ids into hashed-ids
     Ioss::NodeBlock *nb = region_.get_node_blocks()[0];
 
diff --git a/packages/seacas/libraries/ioss/src/Ioss_FaceGenerator.h b/packages/seacas/libraries/ioss/src/Ioss_FaceGenerator.h
index ed9ada94a129..b658e66cd508 100644
--- a/packages/seacas/libraries/ioss/src/Ioss_FaceGenerator.h
+++ b/packages/seacas/libraries/ioss/src/Ioss_FaceGenerator.h
@@ -39,14 +39,20 @@ namespace Ioss {
 
     void add_element(size_t element_id) const
     {
-      if (elementCount_ < 2) {
-        element[elementCount_++] = element_id;
+      assert(element_id != 0);
+      if (element[0] == 0) {
+        element[0] = element_id;
+      }
+      else if (element[1] == 0) {
+        element[1] = element_id;
       }
       else {
         face_element_error(element_id);
       }
     }
 
+    int element_count() const { return (element[0] != 0) + (element[1] != 0); }
+
     void add_element(size_t element_id, size_t face_ordinal) const
     {
       add_element(element_id * 10 + face_ordinal);
@@ -70,7 +76,6 @@ namespace Ioss {
     // parallel communication maps.  May need to save the proc it is
     // shared with also (which is available in git history)
     mutable std::array<size_t, 2> element{};
-    mutable int                   elementCount_{0}; // Should be max of 2 solid elements...
     std::array<size_t, 4>         connectivity_{};
   };
 
@@ -108,7 +113,7 @@ namespace Ioss {
 #if defined FG_USE_STD
   using FaceUnorderedSet = std::unordered_set<Face, FaceHash, FaceEqual>;
 #elif defined FG_USE_HOPSCOTCH
-  //using FaceUnorderedSet = tsl::hopscotch_set<Face, FaceHash, FaceEqual>;
+  // using FaceUnorderedSet = tsl::hopscotch_set<Face, FaceHash, FaceEqual>;
   using FaceUnorderedSet = tsl::hopscotch_pg_set<Face, FaceHash, FaceEqual>;
 #elif defined FG_USE_ROBIN
   //  using FaceUnorderedSet = tsl::robin_set<Face, FaceHash, FaceEqual>;
@@ -130,15 +135,17 @@ namespace Ioss {
     FaceUnorderedSet &faces(const std::string &name = "ALL") { return faces_[name]; }
     FaceUnorderedSet &faces(const ElementBlock *block);
 
-    void clear(const std::string &name)  {faces_[name].clear();}
+    void clear(const std::string &name) { faces_[name].clear(); }
     void clear(const ElementBlock *block);
 
     //! Given a local node id (0-based), return the hashed value.
     size_t node_id_hash(size_t local_node_id) const { return hashIds_[local_node_id]; }
 
+    void progress(const std::string &output) const;
+
   private:
     template <typename INT> void hash_node_ids(const std::vector<INT> &node_ids);
-    void hash_local_node_ids(size_t count);
+    void                         hash_local_node_ids(size_t count);
     template <typename INT> void generate_model_faces(INT /*dummy*/, bool local_ids);
 
     Ioss::Region                           &region_;
diff --git a/packages/seacas/libraries/ioss/src/Ioss_Field.C b/packages/seacas/libraries/ioss/src/Ioss_Field.C
index c110b825c5e9..0e0b33a8bee4 100644
--- a/packages/seacas/libraries/ioss/src/Ioss_Field.C
+++ b/packages/seacas/libraries/ioss/src/Ioss_Field.C
@@ -11,6 +11,7 @@
 #include <cstddef>
 #include <cstdint>
 #include <fmt/ostream.h>
+#include <fmt/ranges.h>
 #include <iostream>
 #include <string>
 #include <vector>
diff --git a/packages/seacas/libraries/ioss/src/Ioss_Field.h b/packages/seacas/libraries/ioss/src/Ioss_Field.h
index 4fd2146c72fb..80c7aae15654 100644
--- a/packages/seacas/libraries/ioss/src/Ioss_Field.h
+++ b/packages/seacas/libraries/ioss/src/Ioss_Field.h
@@ -8,6 +8,9 @@
 
 #include "Ioss_CodeTypes.h"
 #include <cstddef> // for size_t
+#if !defined BUILT_IN_SIERRA
+#include <fmt/ostream.h>
+#endif
 #include <stdint.h>
 #include <string> // for string
 #include <vector> // for vector
@@ -244,3 +247,13 @@ namespace Ioss {
   };
   IOSS_EXPORT std::ostream &operator<<(std::ostream &os, const Field &fld);
 } // namespace Ioss
+
+#if !defined BUILT_IN_SIERRA
+#if FMT_VERSION >= 90000
+namespace fmt {
+  template <> struct formatter<Ioss::Field> : ostream_formatter
+  {
+  };
+} // namespace fmt
+#endif
+#endif
diff --git a/packages/seacas/libraries/ioss/src/Ioss_Glob.h b/packages/seacas/libraries/ioss/src/Ioss_Glob.h
index 58f65a3e561c..6d84314f30f7 100644
--- a/packages/seacas/libraries/ioss/src/Ioss_Glob.h
+++ b/packages/seacas/libraries/ioss/src/Ioss_Glob.h
@@ -225,7 +225,7 @@ namespace Ioss::glob {
     }
 
     std::vector<std::unique_ptr<State<charT>>> states_;
-    size_t                                     match_state_;
+    size_t                                     match_state_{};
 
     size_t start_state_{0};
   };
diff --git a/packages/seacas/libraries/ioss/src/Ioss_IOFactory.C b/packages/seacas/libraries/ioss/src/Ioss_IOFactory.C
index e020d8dd37d8..80d30ac63c6a 100644
--- a/packages/seacas/libraries/ioss/src/Ioss_IOFactory.C
+++ b/packages/seacas/libraries/ioss/src/Ioss_IOFactory.C
@@ -93,7 +93,9 @@ Ioss::DatabaseIO *Ioss::IOFactory::create(const std::string &type, const std::st
     }
   }
   else {
-    auto                my_props(properties);
+    auto my_props(properties);
+    my_props.add(Property("database_type", type));
+
     Ioss::ParallelUtils pu(communicator);
     pu.add_environment_properties(my_props);
     if (my_props.exists("SHOW_CONFIG")) {
diff --git a/packages/seacas/libraries/ioss/src/Ioss_ParallelUtils.h b/packages/seacas/libraries/ioss/src/Ioss_ParallelUtils.h
index 58f5926a9504..24cc545535bd 100644
--- a/packages/seacas/libraries/ioss/src/Ioss_ParallelUtils.h
+++ b/packages/seacas/libraries/ioss/src/Ioss_ParallelUtils.h
@@ -18,6 +18,7 @@
 #if IOSS_DEBUG_OUTPUT
 #include <fmt/format.h>
 #include <fmt/ostream.h>
+#include <fmt/ranges.h>
 #endif
 
 #ifdef SEACAS_HAVE_MPI
diff --git a/packages/seacas/libraries/ioss/src/Ioss_Region.C b/packages/seacas/libraries/ioss/src/Ioss_Region.C
index a3660c18f66c..725d07e9cb12 100644
--- a/packages/seacas/libraries/ioss/src/Ioss_Region.C
+++ b/packages/seacas/libraries/ioss/src/Ioss_Region.C
@@ -20,7 +20,9 @@
 #include "Ioss_FaceBlock.h"
 #include "Ioss_FaceSet.h"
 #include "Ioss_Field.h"
+#include "Ioss_FileInfo.h"
 #include "Ioss_GroupingEntity.h"
+#include "Ioss_IOFactory.h"
 #include "Ioss_NodeBlock.h"
 #include "Ioss_NodeSet.h"
 #include "Ioss_Property.h"
@@ -43,6 +45,11 @@
 #include <tuple>
 #include <vector>
 
+#include <assert.h>
+#include <iomanip>
+#include <iostream>
+#include <sstream>
+
 #include "Ioss_MeshType.h"
 #include "Ioss_ParallelUtils.h"
 
@@ -95,20 +102,30 @@ namespace {
     return count;
   }
 
+  void update_database(Ioss::DatabaseIO *db, Ioss::GroupingEntity *entity)
+  {
+    entity->reset_database(db);
+  }
+
   void update_database(const Ioss::Region *region, Ioss::GroupingEntity *entity)
   {
-    entity->reset_database(region->get_database());
+    update_database(region->get_database(), entity);
   }
 
-  void update_database(const Ioss::Region *region, Ioss::SideSet *sset)
+  void update_database(Ioss::DatabaseIO *db, Ioss::SideSet *sset)
   {
-    sset->reset_database(region->get_database());
+    sset->reset_database(db);
     const auto &blocks = sset->get_side_blocks();
     for (const auto &block : blocks) {
-      block->reset_database(region->get_database());
+      block->reset_database(db);
     }
   }
 
+  void update_database(const Ioss::Region *region, Ioss::SideSet *sset)
+  {
+    update_database(region->get_database(), sset);
+  }
+
   constexpr unsigned numberOfBits(unsigned x) { return x < 2 ? x : 1 + numberOfBits(x >> 1); }
 
   size_t compute_hash(Ioss::GroupingEntity *entity, size_t which)
@@ -348,6 +365,10 @@ namespace Ioss {
     properties.add(Property(this, "state_count", Property::INTEGER));
     properties.add(Property(this, "current_state", Property::INTEGER));
     properties.add(Property(this, "database_name", Property::STRING));
+
+    property_add(Property("base_filename", iodatabase->get_filename()));
+    property_add(Property("database_type",
+                          iodatabase->get_property_manager().get_optional("database_type", "")));
   }
 
   Region::~Region()
@@ -358,63 +379,96 @@ namespace Ioss {
     // Region owns all sub-grouping entities it contains...
     try {
       IOSS_FUNC_ENTER(m_);
-      for (const auto &nb : nodeBlocks) {
-        delete (nb);
-      }
+      reset_region();
 
-      for (const auto &eb : edgeBlocks) {
-        delete (eb);
-      }
+      // Region owns the database pointer even though other entities use it.
+      GroupingEntity::really_delete_database();
+    }
+    catch (...) {
+    }
 
-      for (const auto &fb : faceBlocks) {
-        delete (fb);
-      }
+    if(topologyObserver) {
+      topologyObserver->register_region(nullptr);
+    }
+  }
 
-      for (const auto &eb : elementBlocks) {
-        delete (eb);
-      }
+  void Region::reset_region()
+  {
+    for (const auto &nb : nodeBlocks) {
+      delete (nb);
+    }
+    nodeBlocks.clear();
 
-      for (const auto &sb : structuredBlocks) {
-        delete (sb);
-      }
+    for (const auto &eb : edgeBlocks) {
+      delete (eb);
+    }
+    edgeBlocks.clear();
 
-      for (const auto &ss : sideSets) {
-        delete (ss);
-      }
+    for (const auto &fb : faceBlocks) {
+      delete (fb);
+    }
+    faceBlocks.clear();
 
-      for (const auto &ns : nodeSets) {
-        delete (ns);
-      }
+    for (const auto &eb : elementBlocks) {
+      delete (eb);
+    }
+    elementBlocks.clear();
 
-      for (const auto &es : edgeSets) {
-        delete (es);
-      }
+    for (const auto &sb : structuredBlocks) {
+      delete (sb);
+    }
+    structuredBlocks.clear();
 
-      for (const auto &fs : faceSets) {
-        delete (fs);
-      }
+    for (const auto &ss : sideSets) {
+      delete (ss);
+    }
+    sideSets.clear();
 
-      for (const auto &es : elementSets) {
-        delete (es);
-      }
+    for (const auto &ns : nodeSets) {
+      delete (ns);
+    }
+    nodeSets.clear();
 
-      for (const auto &cs : commSets) {
-        delete (cs);
-      }
+    for (const auto &es : edgeSets) {
+      delete (es);
+    }
+    edgeSets.clear();
 
-      for (const auto &as : assemblies) {
-        delete (as);
-      }
+    for (const auto &fs : faceSets) {
+      delete (fs);
+    }
+    faceSets.clear();
 
-      for (const auto &bl : blobs) {
-        delete (bl);
-      }
+    for (const auto &es : elementSets) {
+      delete (es);
+    }
+    elementSets.clear();
 
-      // Region owns the database pointer even though other entities use it.
-      GroupingEntity::really_delete_database();
+    for (const auto &cs : commSets) {
+      delete (cs);
     }
-    catch (...) {
+    commSets.clear();
+
+    for (const auto &as : assemblies) {
+      delete (as);
     }
+    assemblies.clear();
+
+    for (const auto &bl : blobs) {
+      delete (bl);
+    }
+    blobs.clear();
+
+    stateTimes.clear();
+
+    currentState = -1;
+    stateCount   = 0;
+
+    modelDefined     = false;
+    transientDefined = false;
+
+    // Ioex:DatabaseIO::read_communication_metadata() adds comm fields that need to be cleared
+    erase_fields(Field::COMMUNICATION);
   }
 
   void Region::delete_database() { GroupingEntity::really_delete_database(); }
@@ -652,6 +706,23 @@ namespace Ioss {
       success = set_state(new_state);
     }
     else {
+      bool has_output_observer = topologyObserver && !get_database()->is_input();
+
+      if (new_state == STATE_DEFINE_MODEL) {
+        if (has_output_observer &&
+            (topologyObserver->get_control_option() == FileControlOption::CONTROL_AUTO_GROUP_FILE)) {
+          if (!fileGroupsStarted) {
+            int  steps          = get_property("state_count").get_int();
+            bool force_addition = true;
+            add_output_database_group(steps, force_addition);
+
+            fileGroupsStarted = true;
+          }
+        }
+      }
+      else if (new_state == STATE_TRANSIENT) {
+        update_dynamic_topology();
+      }
       switch (get_state()) {
       case STATE_CLOSED:
         // Make sure we can go to the specified state.
@@ -785,6 +856,12 @@ namespace Ioss {
     else if (current_state == STATE_DEFINE_TRANSIENT) {
       transientDefined = true;
     }
+    else if (current_state == STATE_MODEL) {
+      modelWritten = true;
+    }
+    else if (current_state == STATE_TRANSIENT) {
+      transientWritten = true;
+    }
 
     return success;
   }
@@ -1002,6 +1079,9 @@ namespace Ioss {
         }
         currentState = state;
       }
+
+      update_dynamic_topology();
+
       DatabaseIO *db = get_database();
       db->begin_state(state, time);
     }
@@ -2741,4 +2821,238 @@ namespace Ioss {
     }
   }
 
+  void
+  Region::register_mesh_modification_observer(std::shared_ptr<DynamicTopologyObserver> observer)
+  {
+    if (observer) {
+      if (observer->get_control_option() == FileControlOption::CONTROL_AUTO_GROUP_FILE) {
+        const Ioss::PropertyManager &db_properties = get_database()->get_property_manager();
+        if (!db_properties.exists("ENABLE_FILE_GROUPS")) {
+          std::ostringstream errmsg;
+          fmt::print(errmsg, "ERROR: File groups are not enabled in the database file '{}'.\n",
+                     get_database()->get_filename());
+          IOSS_ERROR(errmsg);
+        }
+      }
+
+      topologyObserver = observer;
+      topologyObserver->register_region(this);
+    }
+  }
+
+  void Region::start_new_output_database_entry(int steps)
+  {
+    if (get_database()->is_input())
+      return;
+
+    if (!topologyObserver)
+      return;
+
+    switch (topologyObserver->get_control_option()) {
+    case FileControlOption::CONTROL_AUTO_MULTI_FILE:
+      clone_and_replace_output_database(steps);
+      break;
+    case FileControlOption::CONTROL_AUTO_GROUP_FILE: add_output_database_group(steps); break;
+    case FileControlOption::CONTROL_NONE:
+    default: return; break;
+    }
+  }
+
+  void Region::add_output_database_group(int steps, bool force_addition)
+  {
+    if (get_database()->is_input())
+      return;
+
+    const Ioss::PropertyManager &db_properties = get_database()->get_property_manager();
+    if (!db_properties.exists("ENABLE_FILE_GROUPS")) {
+      std::ostringstream errmsg;
+      fmt::print(errmsg, "ERROR: File groups are not enabled in the database file '{}'.\n",
+                 get_database()->get_filename());
+      IOSS_ERROR(errmsg);
+    }
+
+    if (topologyObserver &&
+        (topologyObserver->get_control_option() == FileControlOption::CONTROL_AUTO_MULTI_FILE)) {
+      std::ostringstream errmsg;
+      fmt::print(errmsg,
+                 "ERROR: TopologyObserver for database file '{}' does not support file groups.\n",
+                 get_database()->get_filename());
+      IOSS_ERROR(errmsg);
+    }
+
+    int state = steps;
+    if ((topologyObserver && topologyObserver->is_topology_modified()) || force_addition) {
+      // Determine how many steps have been written already...
+      state = get_property("state_count").get_int();
+
+      if (state == 0)
+        state = steps;
+
+      // See if this is a continuation database...
+      if (property_exists("state_offset"))
+        state += get_property("state_offset").get_int();
+
+      state++; // For the state we are going to write.
+
+      reset_region();
+      DynamicTopologyFileControl fileControl(this, fileCyclicCount, ifDatabaseExists,
+                                             dbChangeCount);
+      fileControl.add_output_database_group(state);
+    }
+  }
+
+  void Region::clone_and_replace_output_database(int steps)
+  {
+    if (get_database()->is_input())
+      return;
+
+    if (!topologyObserver)
+      return;
+
+    int state = steps;
+    if (topologyObserver->is_topology_modified() || fileCyclicCount > 0) {
+      // Determine how many steps have been written already...
+      state = get_property("state_count").get_int();
+
+      // Needed for automatic restart... The current database has not
+      // been written to, but we want to open a new one instead of
+      // (possibly) overwriting the current one...
+      // If this is not an automatic restart, then we don't need a new database...
+      if (state == 0 && topologyObserver->is_automatic_restart())
+        return;
+
+      if (topologyObserver->is_automatic_restart() && ifDatabaseExists == Ioss::DB_APPEND)
+        return;
+
+      if (state == 0)
+        state = steps;
+
+      // See if this is a continuation database...
+      if (property_exists("state_offset"))
+        state += get_property("state_offset").get_int();
+
+      state++; // For the state we are going to write.
+
+      reset_region();
+      DynamicTopologyFileControl fileControl(this, fileCyclicCount, ifDatabaseExists,
+                                             dbChangeCount);
+      fileControl.clone_and_replace_output_database(state);
+    }
+  }
+
+  void Region::reset_topology_modification()
+  {
+    if(topologyObserver) {
+      topologyObserver->reset_topology_modification();
+    }
+  }
+
+  void Region::set_topology_modification(unsigned int type)
+  {
+    if(topologyObserver) {
+      topologyObserver->set_topology_modification(type);
+    }
+  }
+
+  unsigned int Region::get_topology_modification() const
+  {
+    if(topologyObserver) {
+      return topologyObserver->get_topology_modification();
+    }
+
+    return TOPOLOGY_SAME;
+  }
+
+  bool Region::load_group_mesh(const std::string &child_group_name)
+  {
+    // Check name for '/' which is not allowed since it is the
+    // separator character in a full group path
+    if (child_group_name.find('/') != std::string::npos) {
+      std::ostringstream errmsg;
+      fmt::print(errmsg, "ERROR: Invalid group name '{}' contains a '/' which is not allowed.\n",
+                 child_group_name);
+      IOSS_ERROR(errmsg);
+    }
+
+    DatabaseIO *iodatabase = get_database();
+
+    if (!iodatabase->is_input())
+      return false;
+
+    if (!iodatabase->open_root_group())
+      return false;
+
+    if (!iodatabase->open_group(child_group_name))
+      return false;
+
+    reset_region();
+    iodatabase->release_memory();
+
+    Region::set_state(STATE_CLOSED);
+    modelDefined     = false;
+    transientDefined = false;
+
+    Region::begin_mode(STATE_DEFINE_MODEL);
+    iodatabase->read_meta_data();
+    Region::end_mode(STATE_DEFINE_MODEL);
+    if (iodatabase->open_create_behavior() != Ioss::DB_APPEND &&
+        iodatabase->open_create_behavior() != Ioss::DB_MODIFY) {
+      modelDefined     = true;
+      transientDefined = true;
+      Region::begin_mode(STATE_READONLY);
+    }
+
+    return true;
+  }
+
+  bool Region::load_group_mesh(const int child_group_index)
+  {
+    DatabaseIO *iodatabase = get_database();
+
+    if (!iodatabase->is_input())
+      return false;
+
+    if (!iodatabase->open_root_group())
+      return false;
+
+    if (!iodatabase->open_child_group(child_group_index))
+      return false;
+
+    reset_region();
+    iodatabase->release_memory();
+
+    Region::set_state(STATE_CLOSED);
+    modelDefined     = false;
+    transientDefined = false;
+
+    Region::begin_mode(STATE_DEFINE_MODEL);
+    iodatabase->read_meta_data();
+    Region::end_mode(STATE_DEFINE_MODEL);
+    if (iodatabase->open_create_behavior() != Ioss::DB_APPEND &&
+        iodatabase->open_create_behavior() != Ioss::DB_MODIFY) {
+      modelDefined     = true;
+      transientDefined = true;
+      Region::begin_mode(STATE_READONLY);
+    }
+
+    return true;
+  }
+
+  void Region::update_dynamic_topology()
+  {
+    auto topologyObserver = get_mesh_modification_observer();
+
+    bool has_output_observer = topologyObserver && !get_database()->is_input();
+    if (has_output_observer && topologyObserver->is_topology_modified()) {
+      if(topologyObserver->get_control_option() != FileControlOption::CONTROL_NONE) {
+        int steps = get_property("state_count").get_int();
+        start_new_output_database_entry(steps);
+
+        topologyObserver->define_model();
+        topologyObserver->write_model();
+        topologyObserver->define_transient();
+      }
+      topologyObserver->reset_topology_modification();
+    }
+  }
 } // namespace Ioss
diff --git a/packages/seacas/libraries/ioss/src/Ioss_Region.h b/packages/seacas/libraries/ioss/src/Ioss_Region.h
index 2b65b19ae4cb..6210b37b2698 100644
--- a/packages/seacas/libraries/ioss/src/Ioss_Region.h
+++ b/packages/seacas/libraries/ioss/src/Ioss_Region.h
@@ -7,8 +7,10 @@
 #pragma once
 
 #include "Ioss_CoordinateFrame.h" // for CoordinateFrame
-#include "Ioss_DatabaseIO.h"      // for DatabaseIO
-#include "Ioss_EntityType.h"      // for EntityType, etc
+#include "Ioss_DBUsage.h"
+#include "Ioss_DatabaseIO.h" // for DatabaseIO
+#include "Ioss_DynamicTopology.h"
+#include "Ioss_EntityType.h" // for EntityType, etc
 #include "Ioss_Field.h"
 #include "Ioss_GroupingEntity.h" // for GroupingEntity
 #include "Ioss_MeshType.h"
@@ -22,9 +24,13 @@
 #include "Ioss_Utils.h"
 #include "Ioss_VariableType.h"
 #include "ioss_export.h"
+#if !defined BUILT_IN_SIERRA
+#include <fmt/ostream.h>
+#endif
 #include <functional> // for less
 #include <iosfwd>     // for ostream
 #include <map>        // for map, map<>::value_compare
+#include <memory>
 #include <sstream>
 #include <string>  // for string, operator<
 #include <utility> // for pair
@@ -52,6 +58,7 @@ namespace Ioss {
 namespace Ioss {
 
   class CoordinateFrame;
+
   enum class MeshType;
 
   using AssemblyContainer = std::vector<Ioss::Assembly *>;
@@ -277,7 +284,40 @@ namespace Ioss {
                                               const std::vector<T *> &entity_container,
                                               std::vector<U>         &field_data) const;
 
+    void register_mesh_modification_observer(std::shared_ptr<DynamicTopologyObserver> observer);
+    std::shared_ptr<DynamicTopologyObserver> get_mesh_modification_observer() const
+    {
+      return topologyObserver;
+    }
+
+    void reset_topology_modification();
+    void set_topology_modification(unsigned int type);
+    unsigned int get_topology_modification() const;
+
+    void start_new_output_database_entry(int steps = 0);
+
+    void         set_topology_change_count(unsigned int new_count) { dbChangeCount = new_count; }
+    unsigned int get_topology_change_count() { return dbChangeCount; }
+
+    void         set_file_cyclic_count(unsigned int new_count) { fileCyclicCount = new_count; }
+    unsigned int get_file_cyclic_count() { return fileCyclicCount; }
+
+    void set_if_database_exists_behavior(IfDatabaseExistsBehavior if_exists)
+    {
+      ifDatabaseExists = if_exists;
+    }
+
+    bool model_is_written() const { return modelWritten; }
+    bool transient_is_written() const { return transientWritten; }
+
+    bool load_group_mesh(const std::string &child_group_name);
+    bool load_group_mesh(const int child_group_index);
+
   protected:
+    void update_dynamic_topology();
+    void clone_and_replace_output_database(int steps = 0);
+    void add_output_database_group(int steps = 0, bool force_addition = false);
+
     int64_t internal_get_field_data(const Field &field, void *data,
                                     size_t data_size = 0) const override;
 
@@ -303,6 +343,7 @@ namespace Ioss {
     bool end_mode_nl(State current_state);
 
     void delete_database() override;
+    void reset_region();
 
     mutable std::map<EntityType, AliasMap> aliases_; ///< Stores alias mappings
 
@@ -329,6 +370,18 @@ namespace Ioss {
     mutable int stateCount{0};
     bool        modelDefined{false};
     bool        transientDefined{false};
+
+    std::shared_ptr<DynamicTopologyObserver> topologyObserver;
+
+    unsigned int dbChangeCount{1}; //!< Used to track number of topology changes.
+    unsigned int fileCyclicCount{
+        0}; //!< For cycling file-A, file-B, file-C, ..., File-A, typically restart only.
+    IfDatabaseExistsBehavior ifDatabaseExists{DB_OVERWRITE};
+
+    bool modelWritten{false};
+    bool transientWritten{false};
+    bool fileGroupsStarted{false};
+
   };
 } // namespace Ioss
 
@@ -431,9 +484,17 @@ namespace Ioss {
 
         if (found && field.get_role() != role) {
           std::ostringstream errmsg;
+#if defined BUILT_IN_SIERRA
           errmsg << "ERROR: Field " << field.get_name() << " with role " << field.role_string()
                  << " on entity " << entity->name() << " does not match previously found role "
                  << Ioss::Field::role_string(role) << ".\n",
+#else
+          fmt::print(errmsg,
+                     "ERROR: Field {} with role {} on entity {} does not match previously found "
+                     "role {}.\n",
+                     field.get_name(), field.role_string(), entity->name(),
+                     Ioss::Field::role_string(role));
+#endif
               IOSS_ERROR(errmsg);
         }
 
diff --git a/packages/seacas/libraries/ioss/src/Ioss_StructuredBlock.C b/packages/seacas/libraries/ioss/src/Ioss_StructuredBlock.C
index 7e06fcb72174..7c8891124a27 100644
--- a/packages/seacas/libraries/ioss/src/Ioss_StructuredBlock.C
+++ b/packages/seacas/libraries/ioss/src/Ioss_StructuredBlock.C
@@ -11,6 +11,7 @@
 #include "Ioss_Hex8.h"
 #include "Ioss_Property.h" // for Property
 #include "Ioss_SmartAssert.h"
+#include "Ioss_Sort.h"
 #include "Ioss_StructuredBlock.h"
 #include <cmath>
 #include <cstddef> // for size_t
@@ -533,25 +534,38 @@ namespace Ioss {
       same = false;
     }
 
-    // NOTE: this comparison assumes that the elements of this vector will
-    // appear in the same order in two databases that are equivalent.
     if (quiet && this->m_zoneConnectivity != rhs.m_zoneConnectivity) {
       return false;
     }
-    if (!vec_equal(this->m_zoneConnectivity, rhs.m_zoneConnectivity)) {
-      fmt::print(Ioss::OUTPUT(), "StructuredBlock: Zone Connectivity mismatch (size {} vs {})\n",
-                 this->m_zoneConnectivity.size(), rhs.m_zoneConnectivity.size());
-      same = false;
+    {
+      auto lhzc = this->m_zoneConnectivity;
+      auto rhzc = rhs.m_zoneConnectivity;
+      Ioss::sort(lhzc.begin(), lhzc.end(), [](const ZoneConnectivity &l, const ZoneConnectivity &r) {
+					    return l.m_connectionName < r.m_connectionName;});
+      Ioss::sort(rhzc.begin(), rhzc.end(), [](const ZoneConnectivity &l, const ZoneConnectivity &r) {
+					    return l.m_connectionName < r.m_connectionName;});
+      if (!vec_equal(lhzc, rhzc)) {
+	fmt::print(Ioss::OUTPUT(), "StructuredBlock: Zone Connectivity mismatch (size {} vs {})\n",
+		   this->m_zoneConnectivity.size(), rhs.m_zoneConnectivity.size());
+	same = false;
+      }
     }
 
-    // NOTE: this comparison assumes that the elements of this vector will
-    // appear in the same order in two databases that are equivalent.
     if (quiet && this->m_boundaryConditions != rhs.m_boundaryConditions) {
       return false;
     }
-    if (!vec_equal(this->m_boundaryConditions, rhs.m_boundaryConditions)) {
-      fmt::print(Ioss::OUTPUT(), "StructuredBlock: Boundary Conditions mismatch\n");
-      same = false;
+
+    {
+      auto lhbc = this->m_boundaryConditions;
+      auto rhbc = rhs.m_boundaryConditions;
+      Ioss::sort(lhbc.begin(), lhbc.end(), [](const BoundaryCondition &l, const BoundaryCondition &r) {
+					    return l.m_bcName < r.m_bcName;});
+      Ioss::sort(rhbc.begin(), rhbc.end(), [](const BoundaryCondition &l, const BoundaryCondition &r) {
+					    return l.m_bcName < r.m_bcName;});
+      if (!vec_equal(lhbc, rhbc)) {
+	fmt::print(Ioss::OUTPUT(), "StructuredBlock: Boundary Conditions mismatch\n");
+	same = false;
+      }
     }
 
     if (!quiet) {
diff --git a/packages/seacas/libraries/ioss/src/Ioss_StructuredBlock.h b/packages/seacas/libraries/ioss/src/Ioss_StructuredBlock.h
index 640e37b8bd45..283b3af21b06 100644
--- a/packages/seacas/libraries/ioss/src/Ioss_StructuredBlock.h
+++ b/packages/seacas/libraries/ioss/src/Ioss_StructuredBlock.h
@@ -12,6 +12,9 @@
 #include "Ioss_NodeBlock.h"
 #include "Ioss_Property.h"
 #include "Ioss_ZoneConnectivity.h"
+#if !defined BUILT_IN_SIERRA
+#include <fmt/ostream.h>
+#endif
 #include <array>
 #include <cassert>
 #include <iosfwd>
@@ -368,3 +371,12 @@ namespace Ioss {
   };
 } // namespace Ioss
 
+#if !defined BUILT_IN_SIERRA
+#if FMT_VERSION >= 90000
+namespace fmt {
+  template <> struct formatter<Ioss::BoundaryCondition> : ostream_formatter
+  {
+  };
+} // namespace fmt
+#endif
+#endif
diff --git a/packages/seacas/libraries/ioss/src/Ioss_Utils.C b/packages/seacas/libraries/ioss/src/Ioss_Utils.C
index eb458f12de08..a61e1d5bd3ca 100644
--- a/packages/seacas/libraries/ioss/src/Ioss_Utils.C
+++ b/packages/seacas/libraries/ioss/src/Ioss_Utils.C
@@ -1369,7 +1369,7 @@ void Ioss::Utils::info_fields(const Ioss::GroupingEntity *ige, Ioss::Field::Role
   for (const auto &field_name : fields) {
     if (detail) {
       const auto &field_ref = ige->get_fieldref(field_name);
-      std::cout << field_ref << suffix;
+      fmt::print("{}{}", field_ref, suffix);
     }
     else {
       const Ioss::VariableType *var_type   = ige->get_field(field_name).raw_storage();
@@ -1377,7 +1377,7 @@ void Ioss::Utils::info_fields(const Ioss::GroupingEntity *ige, Ioss::Field::Role
       fmt::print("{1:>{0}s}:{2}  ", max_width, field_name, comp_count);
       cur_out += max_width + 4;
       if (cur_out + max_width >= width) {
-        fmt::print(suffix);
+        fmt::print("{}", suffix);
         cur_out = 8;
       }
     }
diff --git a/packages/seacas/libraries/ioss/src/Ioss_VariableType.C b/packages/seacas/libraries/ioss/src/Ioss_VariableType.C
index c14a7cfa15bf..21a21216f558 100644
--- a/packages/seacas/libraries/ioss/src/Ioss_VariableType.C
+++ b/packages/seacas/libraries/ioss/src/Ioss_VariableType.C
@@ -18,6 +18,7 @@
 #include <fmt/core.h>
 #include <fmt/format.h>
 #include <fmt/ostream.h>
+#include <fmt/ranges.h>
 #include <map>
 #include <sstream>
 #include <string>
diff --git a/packages/seacas/libraries/ioss/src/Ioss_ZoneConnectivity.h b/packages/seacas/libraries/ioss/src/Ioss_ZoneConnectivity.h
index dda947eb6ee9..1df3ded9432b 100644
--- a/packages/seacas/libraries/ioss/src/Ioss_ZoneConnectivity.h
+++ b/packages/seacas/libraries/ioss/src/Ioss_ZoneConnectivity.h
@@ -10,6 +10,10 @@
 #include <array>
 #include <cassert>
 #include <cmath>
+#if !defined BUILT_IN_SIERRA
+#include <fmt/core.h>
+#include <fmt/ostream.h>
+#endif
 #include <iosfwd>
 #include <stdlib.h>
 #include <string>
@@ -151,3 +155,13 @@ namespace Ioss {
 
   IOSS_EXPORT std::ostream &operator<<(std::ostream &os, const ZoneConnectivity &zgc);
 } // namespace Ioss
+
+#if !defined BUILT_IN_SIERRA
+#if FMT_VERSION >= 90000
+namespace fmt {
+  template <> struct formatter<Ioss::ZoneConnectivity> : ostream_formatter
+  {
+  };
+} // namespace fmt
+#endif
+#endif
diff --git a/packages/seacas/libraries/ioss/src/adios/AdiosWrapper.C b/packages/seacas/libraries/ioss/src/adios/AdiosWrapper.C
index 63de1523f77a..6efb3353dfd2 100644
--- a/packages/seacas/libraries/ioss/src/adios/AdiosWrapper.C
+++ b/packages/seacas/libraries/ioss/src/adios/AdiosWrapper.C
@@ -1,4 +1,4 @@
-// Copyright(C) 1999-2020 National Technology & Engineering Solutions
+// Copyright(C) 1999-2020, 2024 National Technology & Engineering Solutions
 // of Sandia, LLC (NTESS).  Under the terms of Contract DE-NA0003525 with
 // NTESS, the U.S. Government retains certain rights in this software.
 //
@@ -12,9 +12,14 @@ namespace Ioad {
 
   AdiosWrapper::AdiosWrapper(Ioss_MPI_Comm comm, const std::string &filename, bool is_input,
                              unsigned long rank, const Ioss::PropertyManager &properties)
-      : adios2::ADIOS(comm), adios2::IO(IOInit(properties, is_input)),
-        adios2::Engine(EngineInit(filename, is_input)), m_Rank(rank), m_Communicator(comm),
-        m_OpenStep(false)
+#if ADIOS2_USE_MPI
+    : adios2::ADIOS(comm),
+#else
+    : adios2::ADIOS(),
+#endif
+    adios2::IO(IOInit(properties, is_input)),
+    adios2::Engine(EngineInit(filename, is_input)), m_Rank(rank), m_Communicator(comm),
+    m_OpenStep(false)
   {
   }
 
diff --git a/packages/seacas/libraries/ioss/src/adios/AdiosWrapper.hpp b/packages/seacas/libraries/ioss/src/adios/AdiosWrapper.hpp
index 1705d955480a..3cc759cc1d26 100644
--- a/packages/seacas/libraries/ioss/src/adios/AdiosWrapper.hpp
+++ b/packages/seacas/libraries/ioss/src/adios/AdiosWrapper.hpp
@@ -1,4 +1,4 @@
-// Copyright(C) 1999-2020 National Technology & Engineering Solutions
+// Copyright(C) 1999-2020, 2024 National Technology & Engineering Solutions
 // of Sandia, LLC (NTESS).  Under the terms of Contract DE-NA0003525 with
 // NTESS, the U.S. Government retains certain rights in this software.
 //
@@ -15,7 +15,7 @@ namespace Ioad {
   template <typename T>
   void AdiosWrapper::DefineVariable(const std::string &name, const adios2::Dims &shape,
                                     const adios2::Dims &start, const adios2::Dims &count,
-                                    const bool constantDims)
+                                    const bool /*constantDims*/)
   {
     adios2::Variable<T> var = this->IO::InquireVariable<T>(name);
     if (!var) {
diff --git a/packages/seacas/libraries/ioss/src/adios/Ioad_DatabaseIO.h b/packages/seacas/libraries/ioss/src/adios/Ioad_DatabaseIO.h
index 632f5332d2b7..54b0caef8b36 100644
--- a/packages/seacas/libraries/ioss/src/adios/Ioad_DatabaseIO.h
+++ b/packages/seacas/libraries/ioss/src/adios/Ioad_DatabaseIO.h
@@ -60,18 +60,18 @@ namespace Ioad {
                                size_t data_size) const override;
     int64_t get_field_internal(const Ioss::ElementBlock *eb, const Ioss::Field &field, void *data,
                                size_t data_size) const override;
-    int64_t get_field_internal(const Ioss::StructuredBlock *sb, const Ioss::Field &field,
-                               void *data, size_t data_size) const override
+    int64_t get_field_internal(const Ioss::StructuredBlock */* sb */, const Ioss::Field &/*field*/,
+                               void */*data*/, size_t /*data_size*/) const override
     {
       return -1;
     }
-    int64_t get_field_internal(const Ioss::Assembly *sb, const Ioss::Field &field, void *data,
-                               size_t data_size) const override
+    int64_t get_field_internal(const Ioss::Assembly */*sb*/, const Ioss::Field &/*field*/, void */*data*/,
+                               size_t /*data_size*/) const override
     {
       return -1;
     }
-    int64_t get_field_internal(const Ioss::Blob *sb, const Ioss::Field &field, void *data,
-                               size_t data_size) const override
+    int64_t get_field_internal(const Ioss::Blob */*sb*/, const Ioss::Field &/*field*/, void */*data*/,
+                               size_t /*data_size*/) const override
     {
       return -1;
     }
@@ -120,18 +120,18 @@ namespace Ioad {
                                size_t data_size) const override;
     int64_t put_field_internal(const Ioss::CommSet *cs, const Ioss::Field &field, void *data,
                                size_t data_size) const override;
-    int64_t put_field_internal(const Ioss::StructuredBlock *sb, const Ioss::Field &field,
-                               void *data, size_t data_size) const override
+    int64_t put_field_internal(const Ioss::StructuredBlock */*sb*/, const Ioss::Field &/*field*/,
+                               void */*data*/, size_t /*data_size*/) const override
     {
       return -1;
     }
-    int64_t put_field_internal(const Ioss::Assembly *sb, const Ioss::Field &field, void *data,
-                               size_t data_size) const override
+    int64_t put_field_internal(const Ioss::Assembly */*sb*/, const Ioss::Field &/*field*/, void */*data*/,
+                               size_t /*data_size*/) const override
     {
       return -1;
     }
-    int64_t put_field_internal(const Ioss::Blob *sb, const Ioss::Field &field, void *data,
-                               size_t data_size) const override
+    int64_t put_field_internal(const Ioss::Blob */*sb*/, const Ioss::Field &/*field*/, void */*data*/,
+                               size_t /*data_size*/) const override
     {
       return -1;
     }
diff --git a/packages/seacas/libraries/ioss/src/catalyst/Iocatalyst_DatabaseIO.C b/packages/seacas/libraries/ioss/src/catalyst/Iocatalyst_DatabaseIO.C
index e17738a9c63a..379fc673a5bf 100644
--- a/packages/seacas/libraries/ioss/src/catalyst/Iocatalyst_DatabaseIO.C
+++ b/packages/seacas/libraries/ioss/src/catalyst/Iocatalyst_DatabaseIO.C
@@ -39,7 +39,6 @@
 #include <cstdlib>
 #include <fmt/ostream.h>
 #include <map>
-#include <cstdlib>
 
 #include <catalyst.hpp>
 #include <catalyst/Iocatalyst_DatabaseIO.h>
@@ -72,6 +71,8 @@ namespace Iocatalyst {
     inline static const std::string CATCONDNODE        = "CATALYST_CONDUIT_NODE";
     inline static const std::string CATDUMPDIR         = "CATALYST_DATA_DUMP_DIRECTORY";
     inline static const std::string CATREADTIMESTEP    = "CATALYST_READER_TIME_STEP";
+    inline static const std::string CELLIDS            = "cell_ids";
+    inline static const std::string CELLNODEIDS        = "cell_node_ids";
     inline static const std::string COMPONENTCOUNT     = "component_count";
     inline static const std::string COMPONENTDEGREE    = "component_degree";
     inline static const std::string COUNT              = "count";
@@ -588,6 +589,41 @@ namespace Iocatalyst {
 
     std::string getTimePath() { return detail::DATABASE + detail::FS + detail::TIME; }
 
+    int64_t getStructuredBlockIDS(const Ioss::StructuredBlock *sb, const Ioss::Field &field,
+                                  void *data, size_t data_size)
+    {
+      auto num_to_get = field.verify(data_size);
+
+      if (num_to_get > 0) {
+        switch (field.get_type()) {
+        case Ioss::Field::BasicType::INT32:
+          copyIDS(sb, field, reinterpret_cast<int32_t *>(data));
+          break;
+
+        case Ioss::Field::BasicType::INT64:
+          copyIDS(sb, field, reinterpret_cast<int64_t *>(data));
+          break;
+        default:
+          std::ostringstream errmsg;
+          fmt::print(errmsg, "ERROR in {}: {} ({}), unsupported field type: {}\n", __func__,
+                     field.get_name(), num_to_get, field.type_string());
+          IOSS_ERROR(errmsg);
+        }
+      }
+      return num_to_get;
+    }
+
+    template <typename INT_t>
+    void copyIDS(const Ioss::StructuredBlock *sb, const Ioss::Field &field, INT_t *data)
+    {
+      if (field.get_name() == detail::CELLIDS) {
+        sb->get_cell_ids(data, true);
+      }
+      else {
+        sb->get_cell_node_ids(data, true);
+      }
+    }
+
     Ioss::Map &get_node_map(const Ioss::DatabaseIO *dbase) const
     {
       if (this->NodeMap.defined()) {
@@ -1249,13 +1285,20 @@ namespace Iocatalyst {
         if (pm.exists(detail::CATREADTIMESTEP)) {
           timestep = pm.get(detail::CATREADTIMESTEP).get_int();
         }
-        else if(const char* ts = std::getenv(detail::CATREADTIMESTEP.c_str())) {
+        else if (const char *ts = std::getenv(detail::CATREADTIMESTEP.c_str())) {
           timestep = std::stoi(std::string(ts));
         }
+
+        int proc_count = util().parallel_size();
+        int my_proc    = util().parallel_rank();
+        if (properties.exists("processor_count") && properties.exists("my_processor")) {
+          proc_count = properties.get("processor_count").get_int();
+          my_proc    = properties.get("my_processor").get_int();
+        }
+
         std::ostringstream path;
         path << get_catalyst_dump_dir() << detail::EXECUTE_INVC << timestep
-             << detail::PARAMS_CONDUIT_BIN << util().parallel_size() << detail::DOT
-             << util().parallel_rank();
+             << detail::PARAMS_CONDUIT_BIN << proc_count << detail::DOT << my_proc;
         auto &root  = this->Impl->root();
         auto &dbase = this->Impl->databaseNode();
         conduit_node_load(conduit_cpp::c_node(&root), path.str().c_str(), "conduit_bin");
@@ -1673,6 +1716,9 @@ namespace Iocatalyst {
     if (impl.hasField(blockPath, sb, field.get_name())) {
       return impl.getField(blockPath, sb, field, data, data_size);
     }
+    else if (field.get_name() == detail::CELLIDS || field.get_name() == detail::CELLNODEIDS) {
+      return impl.getStructuredBlockIDS(sb, field, data, data_size);
+    }
     else if ((field.get_name() == detail::MESHMODCO) &&
              (impl.hasField(blockPath, sb, detail::MESHMODCOX) &&
               impl.hasField(blockPath, sb, detail::MESHMODCOY) &&
diff --git a/packages/seacas/libraries/ioss/src/catalyst_tests/Iocatalyst_ConduitReadTest.C b/packages/seacas/libraries/ioss/src/catalyst_tests/Iocatalyst_ConduitReadTest.C
index 766a8dc8c16d..48bc67470448 100644
--- a/packages/seacas/libraries/ioss/src/catalyst_tests/Iocatalyst_ConduitReadTest.C
+++ b/packages/seacas/libraries/ioss/src/catalyst_tests/Iocatalyst_ConduitReadTest.C
@@ -9,6 +9,7 @@
 #include <Ioss_StructuredBlock.h>
 #include <catalyst/Iocatalyst_DatabaseIO.h>
 #include <catalyst_tests/Iocatalyst_DatabaseIOTest.h>
+#include <cstdint>
 
 TEST_F(Iocatalyst_DatabaseIOTest, ReadConduitCanExo)
 {
@@ -87,4 +88,47 @@ TEST_F(Iocatalyst_DatabaseIOTest, SetReaderTimeStepWithIOSSEnvVar)
   auto maxt = reg.get_max_time();
   EXPECT_EQ(maxt.first, 1);
   EXPECT_DOUBLE_EQ(maxt.second, 0.0024000538978725672);
+}
+
+TEST_F(Iocatalyst_DatabaseIOTest, SetRankNumRanksSerialParallel)
+{
+  Ioss::PropertyManager iossProp;
+  iossProp.add(Ioss::Property("my_processor", 0));
+  iossProp.add(Ioss::Property("processor_count", 1));
+
+  auto db = getCatalystDatabaseFromConduitFiles("Iocatalyst_can_ex2_MPI_1", iossProp);
+  ASSERT_TRUE(db != nullptr);
+}
+
+TEST_F(Iocatalyst_DatabaseIOTest, CellIdsAndCellNodeIds)
+{
+  setenv("CATALYST_READER_TIME_STEP", "1", 1);
+
+  auto db = getCatalystDatabaseFromConduitFiles("Iocatalyst_sparc1_cgns_MPI_1");
+  ASSERT_TRUE(db != nullptr);
+
+  Ioss::Region reg(db);
+
+  auto sb = reg.get_structured_block("blk-1");
+
+  EXPECT_TRUE(sb->field_exists("cell_ids"));
+  EXPECT_TRUE(sb->field_exists("cell_node_ids"));
+
+  auto cids = sb->get_fieldref("cell_ids");
+  EXPECT_TRUE(cids.get_type() == Ioss::Field::INTEGER);
+  std::vector<int32_t> cidBuff(cids.raw_count());
+  EXPECT_EQ(sb->get_field_data("cell_ids", Data(cidBuff), sizeof(int32_t) * cidBuff.size()),
+            cids.raw_count());
+  EXPECT_EQ(cidBuff[0], 1);
+  EXPECT_EQ(cidBuff[cids.raw_count() - 1], 256);
+
+
+  auto cnids = sb->get_fieldref("cell_node_ids");
+  EXPECT_TRUE(cnids.get_type() == Ioss::Field::INTEGER);
+  std::vector<int32_t> cnidsBuff(cnids.raw_count());
+  EXPECT_EQ(
+      sb->get_field_data("cell_node_ids", Data(cnidsBuff), sizeof(int32_t) * cnidsBuff.size()),
+      cnids.raw_count());
+  EXPECT_EQ(cnidsBuff[0], 1);
+  EXPECT_EQ(cnidsBuff[cnids.raw_count() - 1], 594);
 }
\ No newline at end of file
diff --git a/packages/seacas/libraries/ioss/src/cgns/Iocgns_Utils.C b/packages/seacas/libraries/ioss/src/cgns/Iocgns_Utils.C
index f4fa782a21d5..01a7c4ba557c 100644
--- a/packages/seacas/libraries/ioss/src/cgns/Iocgns_Utils.C
+++ b/packages/seacas/libraries/ioss/src/cgns/Iocgns_Utils.C
@@ -2101,7 +2101,7 @@ void Iocgns::Utils::generate_boundary_faces(
     auto              &boundary = boundary_faces[name];
     auto              &faces    = face_generator.faces(name);
     for (auto &face : faces) {
-      if (face.elementCount_ == 1) {
+      if (face.element_count() == 1) {
         boundary.insert(face);
       }
     }
@@ -3102,7 +3102,7 @@ void Iocgns::Utils::generate_block_faces(Ioss::ElementTopology *topo, size_t num
 
   // All faces generated for this element block; now extract boundary faces...
   for (auto &face : all_faces) {
-    if (face.elementCount_ == 1) {
+    if (face.element_count() == 1) {
       boundary.insert(face);
     }
   }
diff --git a/packages/seacas/libraries/ioss/src/exodus/Ioex_BaseDatabaseIO.C b/packages/seacas/libraries/ioss/src/exodus/Ioex_BaseDatabaseIO.C
index 1e04863d48e7..5cb2caec64e8 100644
--- a/packages/seacas/libraries/ioss/src/exodus/Ioex_BaseDatabaseIO.C
+++ b/packages/seacas/libraries/ioss/src/exodus/Ioex_BaseDatabaseIO.C
@@ -10,6 +10,7 @@
 #include <cstring>
 #include <ctime>
 #include <exodusII.h>
+#include <exodusII_int.h>
 #include <fmt/core.h>
 #include <fmt/ostream.h>
 #include <map>
@@ -17,6 +18,7 @@
 #include <string>
 #include <tokenize.h>
 #include <vector>
+#include <algorithm>
 
 #include "Ioex_Utils.h"
 #include "Ioss_Assembly.h"
@@ -86,6 +88,8 @@ namespace {
   template <typename T>
   void write_attribute_names(int exoid, ex_entity_type type, const std::vector<T *> &entities);
 
+  void query_groups(int exoid, Ioss::NameList& names, bool return_full_names);
+
   class AssemblyTreeFilter
   {
   public:
@@ -257,6 +261,7 @@ namespace Ioex {
 
     // See if there are any properties that need to (or can) be
     // handled prior to opening/creating database...
+#if NC_HAS_HDF5
     bool compress = ((properties.exists("COMPRESSION_LEVEL") &&
                       properties.get("COMPRESSION_LEVEL").get_int() > 0) ||
                      (properties.exists("COMPRESSION_SHUFFLE") &&
@@ -265,24 +270,31 @@ namespace Ioex {
     if (compress) {
       exodusMode |= EX_NETCDF4;
     }
+#endif
 
     if (properties.exists("FILE_TYPE")) {
       std::string type = properties.get("FILE_TYPE").get_string();
       if (type == "netcdf3" || type == "netcdf-3") {
         exodusMode = EX_CLOBBER; // Reset back to default...
       }
+#if NC_HAS_HDF5
       if (type == "netcdf4" || type == "netcdf-4" || type == "hdf5") {
         exodusMode |= EX_NETCDF4;
       }
+#endif
+#if NC_HAS_CDF5
       else if (type == "netcdf5" || type == "netcdf-5" || type == "cdf5") {
         exodusMode |= EX_64BIT_DATA;
       }
+#endif
     }
 
+#if NC_HAS_HDF5
     if (properties.exists("ENABLE_FILE_GROUPS")) {
       exodusMode |= EX_NETCDF4;
       exodusMode |= EX_NOCLASSIC;
     }
+#endif
 
     if (properties.exists("MAXIMUM_NAME_LENGTH")) {
       maximumNameLength = properties.get("MAXIMUM_NAME_LENGTH").get_int();
@@ -490,11 +502,47 @@ namespace Ioex {
     ex_set_max_name_length(m_exodusFilePtr, maximumNameLength);
   }
 
+  bool BaseDatabaseIO::open_root_group_nl()
+  {
+    // Get existing file pointer...
+    bool success = false;
+
+    Ioss::SerializeIO serializeIO_(this);
+    int exoid = get_file_pointer();
+
+    int group_name_length = ex_inquire_int(exoid, EX_INQ_GROUP_NAME_LEN);
+    std::vector<char> group_name(group_name_length+1, '\0');
+
+    // Get name of this group...
+    int   idum;
+    float rdum;
+    int ierr = ex_inquire(exoid, EX_INQ_GROUP_NAME, &idum, &rdum, group_name.data());
+    if (ierr < 0) {
+      std::ostringstream errmsg;
+      fmt::print(errmsg, "ERROR: Could not open root group of group named '{}' in file '{}'.\n", m_groupName,
+                 get_filename());
+      IOSS_ERROR(errmsg);
+    }
+
+    m_groupName = std::string(group_name.data());
+    m_exodusFilePtr = ex_inquire_int(exoid, EX_INQ_GROUP_ROOT);
+
+    if (m_exodusFilePtr < 0) {
+      std::ostringstream errmsg;
+      fmt::print(errmsg, "ERROR: Could not open group named '{}' in file '{}'.\n", m_groupName,
+                 get_filename());
+      IOSS_ERROR(errmsg);
+    }
+    success = true;
+    return success;
+  }
+
   bool BaseDatabaseIO::open_group_nl(const std::string &group_name)
   {
     // Get existing file pointer...
     bool success = false;
 
+    Ioss::SerializeIO serializeIO_(this);
     int exoid = get_file_pointer();
 
     m_groupName = group_name;
@@ -515,6 +563,7 @@ namespace Ioex {
     bool success = false;
     if (!is_input()) {
       // Get existing file pointer...
+      Ioss::SerializeIO serializeIO_(this);
       int exoid = get_file_pointer();
 
       // Check name for '/' which is not allowed since it is the
@@ -1994,7 +2043,7 @@ namespace Ioex {
       bool do_metadata = true;
       Ioss::Utils::check_set_bool_property(properties, "OUTPUT_FIELD_METADATA", do_metadata);
       if (do_metadata) {
-         output_field_metadata();
+        output_field_metadata();
       }
     }
   }
@@ -2006,107 +2055,112 @@ namespace Ioex {
       // Get all transient fields on this entity...
       char default_separator = entity->get_database()->get_field_separator();
       auto results_fields    = entity->field_describe(Ioss::Field::TRANSIENT);
-      for (const auto &field_name : results_fields) {
+
+      std::vector<ex_field> exo_fields(results_fields.size());
+      for (const auto &[i, field_name] : Ioss::enumerate(results_fields)) {
+        exo_fields[i].type[0] = EX_SCALAR;
+
         const auto &field = entity->get_fieldref(field_name);
 
-        ex_field exo_field{};
-        Ioss::Utils::copy_string(exo_field.name, field_name);
-        exo_field.entity_type = type;
-        exo_field.entity_id   = entity->get_optional_property("id", 0);
+        Ioss::Utils::copy_string(exo_fields[i].name, field_name);
+        exo_fields[i].entity_type = type;
+        exo_fields[i].entity_id   = entity->get_optional_property("id", 0);
 
         auto *storage      = field.transformed_storage();
         auto  storage_type = storage->type();
 
         if (storage_type == Ioss::VariableType::Type::COMPOSED) {
-          exo_field.nesting = 2;
+          exo_fields[i].nesting = 2;
 
           const auto *composed = dynamic_cast<const Ioss::ComposedVariableType *>(storage);
           assert(composed != nullptr);
-          exo_field.type[0]                = Ioex::map_ioss_field_type(composed->get_base_type());
-          exo_field.cardinality[0]         = composed->get_base_type()->component_count();
-          char separator0                  = field.get_suffix_separator();
-          exo_field.component_separator[0] = separator0 == 1 ? default_separator : separator0;
+          exo_fields[i].type[0]        = Ioex::map_ioss_field_type(composed->get_base_type());
+          exo_fields[i].cardinality[0] = composed->get_base_type()->component_count();
+          char separator0              = field.get_suffix_separator();
+          exo_fields[i].component_separator[0] = separator0 == 1 ? default_separator : separator0;
 
-          if (exo_field.type[0] == EX_FIELD_TYPE_USER_DEFINED) {
+          if (exo_fields[i].type[0] == EX_FIELD_TYPE_USER_DEFINED) {
             assert(composed->get_base_type()->type() == Ioss::VariableType::Type::NAMED_SUFFIX);
             auto nsvt =
                 dynamic_cast<const Ioss::NamedSuffixVariableType *>(composed->get_base_type());
             assert(nsvt != nullptr);
             std::string suffices{};
-            for (int i = 0; i < nsvt->component_count(); i++) {
-              if (i > 0) {
+            for (int ii = 0; ii < nsvt->component_count(); ii++) {
+              if (ii > 0) {
                 suffices += ",";
               }
-              suffices += nsvt->label(i + 1, 0);
+              suffices += nsvt->label(ii + 1, 0);
             }
-            Ioss::Utils::copy_string(exo_field.suffices, suffices.c_str(), EX_MAX_NAME + 1);
+            Ioss::Utils::copy_string(exo_fields[i].suffices, suffices.c_str(), EX_MAX_NAME + 1);
           }
 
-          exo_field.type[1]        = Ioex::map_ioss_field_type(composed->get_secondary_type());
-          exo_field.cardinality[1] = composed->get_secondary_type()->component_count();
-          char separator1          = field.get_suffix_separator(1);
-          exo_field.component_separator[1] = separator1 == 1 ? default_separator : separator1;
-          if (exo_field.type[1] == EX_BASIS || exo_field.type[1] == EX_QUADRATURE) {
-            exo_field.type_name[0] = ',';
-            Ioss::Utils::copy_string(&exo_field.type_name[1],
+          exo_fields[i].type[1]        = Ioex::map_ioss_field_type(composed->get_secondary_type());
+          exo_fields[i].cardinality[1] = composed->get_secondary_type()->component_count();
+          char separator1              = field.get_suffix_separator(1);
+          exo_fields[i].component_separator[1] = separator1 == 1 ? default_separator : separator1;
+          if (exo_fields[i].type[1] == EX_BASIS || exo_fields[i].type[1] == EX_QUADRATURE) {
+            exo_fields[i].type_name[0] = ',';
+            Ioss::Utils::copy_string(&exo_fields[i].type_name[1],
                                      composed->get_secondary_type()->name(), EX_MAX_NAME);
           }
         }
         else if (storage_type == Ioss::VariableType::Type::COMPOSITE) {
-          exo_field.nesting = 2;
+          exo_fields[i].nesting = 2;
 
           const auto *composite = dynamic_cast<const Ioss::CompositeVariableType *>(storage);
           assert(composite != nullptr);
-          exo_field.type[0]                = Ioex::map_ioss_field_type(composite->get_base_type());
-          exo_field.cardinality[0]         = composite->get_base_type()->component_count();
-          char separator0                  = field.get_suffix_separator();
-          exo_field.component_separator[0] = separator0 == 1 ? default_separator : separator0;
+          exo_fields[i].type[0]        = Ioex::map_ioss_field_type(composite->get_base_type());
+          exo_fields[i].cardinality[0] = composite->get_base_type()->component_count();
+          char separator0              = field.get_suffix_separator();
+          exo_fields[i].component_separator[0] = separator0 == 1 ? default_separator : separator0;
 
-          exo_field.type[1]                = EX_FIELD_TYPE_SEQUENCE;
-          exo_field.cardinality[1]         = composite->get_num_copies();
-          char separator1                  = field.get_suffix_separator(1);
-          exo_field.component_separator[1] = separator1 == 1 ? default_separator : separator1;
+          exo_fields[i].type[1]                = EX_FIELD_TYPE_SEQUENCE;
+          exo_fields[i].cardinality[1]         = composite->get_num_copies();
+          char separator1                      = field.get_suffix_separator(1);
+          exo_fields[i].component_separator[1] = separator1 == 1 ? default_separator : separator1;
         }
         else {
-          exo_field.nesting = 1;
-          exo_field.type[0] = Ioex::map_ioss_field_type(storage);
-          if (exo_field.type[0] == EX_FIELD_TYPE_SEQUENCE) {
-            exo_field.cardinality[0] = storage->component_count();
+          exo_fields[i].nesting = 1;
+          exo_fields[i].type[0] = Ioex::map_ioss_field_type(storage);
+          if (exo_fields[i].type[0] == EX_FIELD_TYPE_SEQUENCE) {
+            exo_fields[i].cardinality[0] = storage->component_count();
           }
-          if (exo_field.type[0] == EX_BASIS) {
+          if (exo_fields[i].type[0] == EX_BASIS) {
             assert(storage->type() == Ioss::VariableType::Type::BASIS);
             const auto *basis = dynamic_cast<const Ioss::BasisVariableType *>(storage);
             assert(basis != nullptr);
-            exo_field.cardinality[0] = storage->component_count();
-            Ioss::Utils::copy_string(exo_field.type_name, basis->name());
+            exo_fields[i].cardinality[0] = storage->component_count();
+            Ioss::Utils::copy_string(exo_fields[i].type_name, basis->name());
           }
-          if (exo_field.type[0] == EX_QUADRATURE) {
+          if (exo_fields[i].type[0] == EX_QUADRATURE) {
             assert(storage->type() == Ioss::VariableType::Type::QUADRATURE);
             const auto *quad = dynamic_cast<const Ioss::QuadratureVariableType *>(storage);
             assert(quad != nullptr);
-            exo_field.cardinality[0] = storage->component_count();
-            Ioss::Utils::copy_string(exo_field.type_name, quad->name());
+            exo_fields[i].cardinality[0] = storage->component_count();
+            Ioss::Utils::copy_string(exo_fields[i].type_name, quad->name());
           }
-          if (exo_field.type[0] == EX_FIELD_TYPE_USER_DEFINED) {
+          if (exo_fields[i].type[0] == EX_FIELD_TYPE_USER_DEFINED) {
             assert(storage->type() == Ioss::VariableType::Type::NAMED_SUFFIX);
             auto nsvt = dynamic_cast<const Ioss::NamedSuffixVariableType *>(storage);
             assert(nsvt != nullptr);
-            exo_field.cardinality[0] = nsvt->component_count();
+            exo_fields[i].cardinality[0] = nsvt->component_count();
             std::string suffices{};
-            for (int i = 0; i < nsvt->component_count(); i++) {
-              if (i > 0) {
+            for (int ii = 0; ii < nsvt->component_count(); ii++) {
+              if (ii > 0) {
                 suffices += ",";
               }
-              suffices += nsvt->label(i + 1, 0);
+              suffices += nsvt->label(ii + 1, 0);
             }
-            Ioss::Utils::copy_string(exo_field.suffices, suffices.c_str(), EX_MAX_NAME + 1);
+            Ioss::Utils::copy_string(exo_fields[i].suffices, suffices.c_str(), EX_MAX_NAME + 1);
           }
-          char separator                   = field.get_suffix_separator();
-          exo_field.component_separator[0] = separator == 1 ? default_separator : separator;
+          char separator                       = field.get_suffix_separator();
+          exo_fields[i].component_separator[0] = separator == 1 ? default_separator : separator;
         }
+      }
 
+      ex_put_multi_field_metadata(exoid, Data(exo_fields), exo_fields.size());
+      for (const auto &exo_field : exo_fields) {
         if (exo_field.type[0] != EX_SCALAR) {
-          ex_put_field_metadata(exoid, exo_field);
           if (exo_field.type[0] == EX_FIELD_TYPE_USER_DEFINED) {
             ex_put_field_suffices(exoid, exo_field, exo_field.suffices);
           }
@@ -2182,6 +2236,7 @@ namespace Ioex {
   {
     Ioss::SerializeIO serializeIO_(this);
     // Output the 'basis' and 'quadrature' type metadata...
+    exi_persist_redef(get_file_pointer(), __func__);
     output_type_metadata(get_file_pointer());
 
     const Ioss::NodeBlockContainer &node_blocks = get_region()->get_node_blocks();
@@ -2217,6 +2272,7 @@ namespace Ioex {
 
     const Ioss::SideSetContainer &sidesets = get_region()->get_sidesets();
     internal_output_field_metadata(get_file_pointer(), EX_SIDE_SET, sidesets);
+    exi_persist_leavedef(get_file_pointer(), __func__);
   }
 
   // common
@@ -3164,6 +3220,87 @@ namespace Ioex {
     // Write coordinate frame data...
     write_coordinate_frames(get_file_pointer(), get_region()->get_coordinate_frames());
   }
+
+
+  Ioss::NameList BaseDatabaseIO::groups_describe_nl(bool return_full_names)
+  {
+    Ioss::SerializeIO serializeIO_(this);
+
+    Ioss::NameList names;
+    int group_root = ex_inquire_int(get_file_pointer(), EX_INQ_GROUP_ROOT);
+    query_groups(group_root, names, return_full_names);
+
+    return names;
+  }
+
+  void BaseDatabaseIO::release_memory_nl()
+  {
+    Ioss::DatabaseIO::release_memory_nl();
+
+    ids_.clear();
+    m_groupCount.clear();
+
+    nodeCmapIds.clear();
+    nodeCmapNodeCnts.clear();
+    elemCmapIds.clear();
+    elemCmapElemCnts.clear();
+
+    m_truthTable.clear();
+    m_variables.clear();
+    m_reductionVariables.clear();
+
+    m_reductionValues.clear();
+
+    nodeConnectivityStatus.clear();
+
+    activeNodeSetNodesIndex.clear();
+  }
+
+  int BaseDatabaseIO::num_child_group_nl()
+  {
+    Ioss::SerializeIO serializeIO_(this);
+    int exoid = get_file_pointer();
+    exoid = ex_inquire_int(exoid, EX_INQ_GROUP_ROOT);
+    int num_children = ex_inquire_int(exoid, EX_INQ_NUM_CHILD_GROUPS);
+    return num_children;
+  }
+
+  bool BaseDatabaseIO::open_child_group_nl(int index)
+  {
+    if(index < 0) return false;
+    Ioss::SerializeIO serializeIO_(this);
+    int exoid = get_file_pointer();
+    int num_children = ex_inquire_int(exoid, EX_INQ_NUM_CHILD_GROUPS);
+    if(num_children == 0) return true;
+
+    if(index >= num_children) return false;
+
+    std::vector<int> children(num_children);
+
+    int ierr = ex_get_group_ids(exoid, nullptr, Data(children));
+    if (ierr < 0) {
+      Ioex::exodus_error(exoid, __LINE__, __func__, __FILE__);
+    }
+
+    exoid = children[index];
+
+    int group_name_length = ex_inquire_int(exoid, EX_INQ_GROUP_NAME_LEN);
+    std::vector<char> group_name(group_name_length+1, '\0');
+
+    // Get name of this group...
+    int   idum;
+    float rdum;
+    ierr = ex_inquire(exoid, EX_INQ_GROUP_NAME, &idum, &rdum, group_name.data());
+    if (ierr < 0) {
+      Ioex::exodus_error(exoid, __LINE__, __func__, __FILE__);
+    }
+
+    m_exodusFilePtr = exoid;
+    m_groupName = std::string(group_name.data());
+
+    return true;
+  }
+
 } // namespace Ioex
 
 namespace {
@@ -3465,4 +3602,41 @@ namespace {
     }
 #endif
   }
+
+  void query_groups(int exoid, Ioss::NameList& names, bool return_full_names)
+  {
+    int   idum;
+    float rdum;
+
+    int group_name_length = ex_inquire_int(exoid, EX_INQ_GROUP_NAME_LEN);
+    std::vector<char> group_name(group_name_length+1, '\0');
+
+    // Get name of this group...
+    int ierr = ex_inquire(exoid, EX_INQ_GROUP_NAME, &idum, &rdum, group_name.data());
+    if (ierr < 0) {
+      Ioex::exodus_error(exoid, __LINE__, __func__, __FILE__);
+    }
+
+    if(return_full_names) {
+      std::fill(group_name.begin(), group_name.end(), '\0');
+      ierr = ex_inquire(exoid, EX_INQ_FULL_GROUP_NAME, &idum, &rdum, group_name.data());
+      if (ierr < 0) {
+        Ioex::exodus_error(exoid, __LINE__, __func__, __FILE__);
+      }
+      names.push_back(std::string(group_name.data()));
+    } else {
+      names.push_back(std::string(group_name.data()));
+    }
+
+    int              num_children = ex_inquire_int(exoid, EX_INQ_NUM_CHILD_GROUPS);
+    std::vector<int> children(num_children);
+    ierr = ex_get_group_ids(exoid, nullptr, Data(children));
+    if (ierr < 0) {
+      Ioex::exodus_error(exoid, __LINE__, __func__, __FILE__);
+    }
+
+    for (int i = 0; i < num_children; i++) {
+      query_groups(children[i], names, return_full_names);
+    }
+  }
 } // namespace
diff --git a/packages/seacas/libraries/ioss/src/exodus/Ioex_BaseDatabaseIO.h b/packages/seacas/libraries/ioss/src/exodus/Ioex_BaseDatabaseIO.h
index 1d05234f8a90..b6f18fc75653 100644
--- a/packages/seacas/libraries/ioss/src/exodus/Ioex_BaseDatabaseIO.h
+++ b/packages/seacas/libraries/ioss/src/exodus/Ioex_BaseDatabaseIO.h
@@ -99,8 +99,14 @@ namespace Ioex {
     IOSS_NODISCARD bool ok_nl(bool write_message = false, std::string *error_message = nullptr,
                               int *bad_count = nullptr) const override;
 
+    void release_memory_nl() override;
+
+    int  num_child_group_nl() override;
+    bool open_child_group_nl(int index) override;
+    bool open_root_group_nl() override;
     bool open_group_nl(const std::string &group_name) override;
     bool create_subgroup_nl(const std::string &group_name) override;
+    Ioss::NameList groups_describe_nl(bool return_full_names) override;
 
     bool begin_nl(Ioss::State state) override;
     bool end_nl(Ioss::State state) override;
@@ -320,6 +326,7 @@ namespace Ioex {
 
     time_t timeLastFlush{0};
     int    flushInterval{-1};
+    int    m_timestepCount{0};
 
     mutable bool fileExists{false}; // False if file has never been opened/created
     mutable bool minimizeOpenFiles{false};
diff --git a/packages/seacas/libraries/ioss/src/exodus/Ioex_DatabaseIO.C b/packages/seacas/libraries/ioss/src/exodus/Ioex_DatabaseIO.C
index 5e0540cc7ef5..d368bd2ff93d 100644
--- a/packages/seacas/libraries/ioss/src/exodus/Ioex_DatabaseIO.C
+++ b/packages/seacas/libraries/ioss/src/exodus/Ioex_DatabaseIO.C
@@ -171,6 +171,9 @@ namespace Ioex {
         IOSS_ERROR(errmsg);
       }
     }
+
+    open_root_group_nl();
+    open_child_group_nl(0);
   }
 
   bool DatabaseIO::check_valid_file_ptr(bool write_message, std::string *error_msg, int *bad_count,
@@ -642,13 +645,12 @@ namespace Ioex {
   {
     bool                exists         = false;
     double              last_time      = DBL_MAX;
-    int                 timestep_count = 0;
     std::vector<double> tsteps(0);
 
     if (dbUsage == Ioss::WRITE_HISTORY) {
       if (myProcessor == 0) {
-        timestep_count = ex_inquire_int(get_file_pointer(), EX_INQ_TIME);
-        if (timestep_count <= 0) {
+        m_timestepCount = ex_inquire_int(get_file_pointer(), EX_INQ_TIME);
+        if (m_timestepCount <= 0) {
           return;
         }
 
@@ -657,15 +659,15 @@ namespace Ioex {
         // Read the timesteps and add them to the region.
         // Since we can't access the Region's stateCount directly, we just add
         // all of the steps and assume the Region is dealing with them directly...
-        tsteps.resize(timestep_count);
+        tsteps.resize(m_timestepCount);
 
         int error = ex_get_all_times(get_file_pointer(), Data(tsteps));
         if (error < 0) {
           Ioex::exodus_error(get_file_pointer(), __LINE__, __func__, __FILE__);
         }
 
-        int max_step = properties.get_optional("APPEND_OUTPUT_AFTER_STEP", timestep_count);
-        max_step     = std::min(max_step, timestep_count);
+        int max_step = properties.get_optional("APPEND_OUTPUT_AFTER_STEP", m_timestepCount);
+        max_step     = std::min(max_step, m_timestepCount);
 
         double max_time =
             properties.get_optional("APPEND_OUTPUT_AFTER_TIME", std::numeric_limits<double>::max());
@@ -681,14 +683,32 @@ namespace Ioex {
     else {
       {
         Ioss::SerializeIO serializeIO_(this);
-        timestep_count = ex_inquire_int(get_file_pointer(), EX_INQ_TIME);
-        if (timestep_count <= 0) {
+        m_timestepCount = ex_inquire_int(get_file_pointer(), EX_INQ_TIME);
+	// Need to sync timestep count across ranks if parallel...
+	if (isParallel) {
+	  auto min_timestep_count = util().global_minmax(m_timestepCount, Ioss::ParallelUtils::DO_MIN);
+	  if (min_timestep_count == 0) {
+	    auto max_timestep_count = util().global_minmax(m_timestepCount, Ioss::ParallelUtils::DO_MAX);
+	    if (max_timestep_count != 0) {
+	      if (myProcessor == 0) {
+		// NOTE: Don't want to warn on all processors if the
+		// timestep count is zero on some, but not all ranks.
+		fmt::print(Ioss::WarnOut(),
+			   "At least one database has no timesteps.  No times will be read on ANY"
+			   " database for consistency.\n");
+	      }
+	    }
+	  }
+	  m_timestepCount = min_timestep_count;
+	}
+	
+        if (m_timestepCount <= 0) {
           return;
         }
 
         // For an exodus file, timesteps are global and are stored in the region.
         // Read the timesteps and add to the region
-        tsteps.resize(timestep_count, -std::numeric_limits<double>::max());
+        tsteps.resize(m_timestepCount, -std::numeric_limits<double>::max());
 
         // The `EXODUS_CALL_GET_ALL_TIMES=NO` is typically only used in
         // isSerialParallel mode and the client is responsible for
@@ -734,8 +754,8 @@ namespace Ioex {
       // One use case is that job is restarting at a time prior to what has been
       // written to the results file, so want to start appending after
       // restart time instead of at end time on database.
-      int max_step = properties.get_optional("APPEND_OUTPUT_AFTER_STEP", timestep_count);
-      max_step     = std::min(max_step, timestep_count);
+      int max_step = properties.get_optional("APPEND_OUTPUT_AFTER_STEP", m_timestepCount);
+      max_step     = std::min(max_step, m_timestepCount);
 
       double max_time =
           properties.get_optional("APPEND_OUTPUT_AFTER_TIME", std::numeric_limits<double>::max());
@@ -1125,12 +1145,11 @@ namespace Ioex {
     Ioss::Int64Vector counts(m_groupCount[entity_type] * 4);
     Ioss::Int64Vector local_X_count(m_groupCount[entity_type]);
     Ioss::Int64Vector global_X_count(m_groupCount[entity_type]);
-    int               iblk;
 
     {
       Ioss::SerializeIO serializeIO_(this);
 
-      for (iblk = 0; iblk < m_groupCount[entity_type]; iblk++) {
+      for (int iblk = 0; iblk < m_groupCount[entity_type]; iblk++) {
         int     index = 4 * iblk;
         int64_t id    = X_block_ids[iblk];
 
@@ -1184,7 +1203,7 @@ namespace Ioex {
                                                 // querying if none.
     int nmap = std::numeric_limits<int>::max(); // Number of 'block' vars on database. Used to skip
                                                 // querying if none.
-    for (iblk = 0; iblk < m_groupCount[entity_type]; iblk++) {
+    for (int iblk = 0; iblk < m_groupCount[entity_type]; iblk++) {
       int     index       = 4 * iblk;
       int64_t nodes_per_X = counts[index + 0];
       int64_t edges_per_X = counts[index + 1];
diff --git a/packages/seacas/libraries/ioss/src/exodus/Ioex_ParallelDatabaseIO.C b/packages/seacas/libraries/ioss/src/exodus/Ioex_ParallelDatabaseIO.C
index b0d9f4304d36..8ce9dd59b7bd 100644
--- a/packages/seacas/libraries/ioss/src/exodus/Ioex_ParallelDatabaseIO.C
+++ b/packages/seacas/libraries/ioss/src/exodus/Ioex_ParallelDatabaseIO.C
@@ -793,10 +793,9 @@ namespace Ioex {
     Ioex::read_exodus_basis(exoid);
     Ioex::read_exodus_quadrature(exoid);
 
-    get_elemblocks();
-
     get_step_times_nl();
 
+    get_elemblocks();
     get_nodeblocks();
     get_edgeblocks();
     get_faceblocks();
@@ -922,6 +921,7 @@ namespace Ioex {
 
     {
       timestep_count = ex_inquire_int(get_file_pointer(), EX_INQ_TIME);
+      m_timestepCount = timestep_count;
       if (timestep_count <= 0) {
         return;
       }
diff --git a/packages/seacas/libraries/ioss/src/exodus/Ioex_Utils.C b/packages/seacas/libraries/ioss/src/exodus/Ioex_Utils.C
index d922e6fafd35..12ac92d9e6b0 100644
--- a/packages/seacas/libraries/ioss/src/exodus/Ioex_Utils.C
+++ b/packages/seacas/libraries/ioss/src/exodus/Ioex_Utils.C
@@ -17,6 +17,7 @@
 #include <iosfwd>
 #include <netcdf.h>
 #include <tokenize.h>
+#include <strings.h>
 
 #include "Ioss_BasisVariableType.h"
 #include "Ioss_CoordinateFrame.h"
@@ -616,7 +617,7 @@ namespace Ioex {
     // Try to decode an id from the name.
     std::string name_string = entity->get_property(prop_name).get_string();
     std::string type_name   = entity->short_type_string();
-    if (std::strncmp(type_name.c_str(), name_string.c_str(), type_name.size()) == 0) {
+    if (strncasecmp(type_name.c_str(), name_string.c_str(), type_name.size()) == 0) {
       id = extract_id(name_string);
       if (id <= 0) {
         id = 1;
diff --git a/packages/seacas/libraries/ioss/src/exonull/Ioexnl_DecompositionData.C b/packages/seacas/libraries/ioss/src/exonull/Ioexnl_DecompositionData.C
index 84848ee2bc0c..2354423d1774 100644
--- a/packages/seacas/libraries/ioss/src/exonull/Ioexnl_DecompositionData.C
+++ b/packages/seacas/libraries/ioss/src/exonull/Ioexnl_DecompositionData.C
@@ -1,4 +1,4 @@
-// Copyright(C) 1999-2023 National Technology & Engineering Solutions
+// Copyright(C) 1999-2024 National Technology & Engineering Solutions
 // of Sandia, LLC (NTESS).  Under the terms of Contract DE-NA0003525 with
 // NTESS, the U.S. Government retains certain rights in this software.
 //
@@ -7,26 +7,16 @@
 #include "Ioss_CodeTypes.h"
 #include "exonull/Ioexnl_DecompositionData.h"
 #if defined PARALLEL_AWARE_EXODUS
-#include "Ioss_ElementTopology.h" // for ElementTopology
 #include "Ioss_Field.h"           // for Field, etc
 #include "Ioss_Map.h"             // for Map, MapContainer
 #include "Ioss_PropertyManager.h" // for PropertyManager
-#include "Ioss_SmartAssert.h"
-#include "Ioss_Sort.h"
 #include "Ioss_Utils.h"
 #include "exonull/Ioexnl_Utils.h"
 
 #include <algorithm>
-#include <cassert>
 #include <climits>
-#include <cmath>
 #include <cstdlib>
-#include <cstring>
-#include <fmt/ostream.h>
-#include <iostream>
 #include <iterator>
-#include <map>
-#include <numeric>
 #include <utility>
 
 namespace Ioexnl {
diff --git a/packages/seacas/libraries/ioss/src/exonull/Ioexnl_DecompositionData.h b/packages/seacas/libraries/ioss/src/exonull/Ioexnl_DecompositionData.h
index 603627bca150..4ac731d1e70e 100644
--- a/packages/seacas/libraries/ioss/src/exonull/Ioexnl_DecompositionData.h
+++ b/packages/seacas/libraries/ioss/src/exonull/Ioexnl_DecompositionData.h
@@ -11,24 +11,18 @@
 #if defined PARALLEL_AWARE_EXODUS
 
 #include "Ioss_CodeTypes.h"
+#include <string>
 #include <vector>
 
 #include "ioexnl_export.h"
-#if !defined(NO_PARMETIS_SUPPORT)
-#include <parmetis.h>
-#endif
 
-#undef MPICPP
-#if !defined(NO_ZOLTAN_SUPPORT)
-#include <zoltan_cpp.h>
-#endif
 #include "Ioss_Decomposition.h"
-#include "Ioss_Map.h"
-#include "Ioss_PropertyManager.h"
 
 namespace Ioss {
   class Field;
-}
+  class Map;
+  class PropertyManager;
+} // namespace Ioss
 namespace Ioexnl {
 
   class IOEXNL_EXPORT DecompositionDataBase
diff --git a/packages/seacas/libraries/ioss/src/faodel/Iofaodel_FieldSerialization.h b/packages/seacas/libraries/ioss/src/faodel/Iofaodel_FieldSerialization.h
index 50ab629d1bdf..28bbc4229fe4 100644
--- a/packages/seacas/libraries/ioss/src/faodel/Iofaodel_FieldSerialization.h
+++ b/packages/seacas/libraries/ioss/src/faodel/Iofaodel_FieldSerialization.h
@@ -1,4 +1,4 @@
-// Copyright(C) 1999-2022 National Technology & Engineering Solutions
+// Copyright(C) 1999-2022, 2024 National Technology & Engineering Solutions
 // of Sandia, LLC (NTESS).  Under the terms of Contract DE-NA0003525 with
 // NTESS, the U.S. Government retains certain rights in this software.
 //
@@ -40,7 +40,7 @@ namespace Iofaodel {
   IOFAODEL_EXPORT size_t data_size(const Ioss::Field &f);
 
   // Caller should write their own version of this
-  // FieldFunction should return a function or a lamba that matches the
+  // FieldFunction should return a function or a lambda that matches the
   // signature below. The function it returns may or may not capture variables
   // that are given to the user-defined function.
   // Some examples are given in this file and are also useful
diff --git a/packages/seacas/libraries/ioss/src/faodel/Iofaodel_PropertySerialization.h b/packages/seacas/libraries/ioss/src/faodel/Iofaodel_PropertySerialization.h
index 68ac3d42372d..50c2fefaa21d 100644
--- a/packages/seacas/libraries/ioss/src/faodel/Iofaodel_PropertySerialization.h
+++ b/packages/seacas/libraries/ioss/src/faodel/Iofaodel_PropertySerialization.h
@@ -1,4 +1,4 @@
-// Copyright(C) 1999-2022 National Technology & Engineering Solutions
+// Copyright(C) 1999-2022, 2024 National Technology & Engineering Solutions
 // of Sandia, LLC (NTESS).  Under the terms of Contract DE-NA0003525 with
 // NTESS, the U.S. Government retains certain rights in this software.
 //
@@ -23,7 +23,7 @@ namespace Iofaodel {
   IOFAODEL_EXPORT size_t data_size(const Ioss::Property &p);
 
   // Caller should write their own version of this
-  // PropertyFunction should return a function or a lamba that matches the
+  // PropertyFunction should return a function or a lambda that matches the
   // signature below. The function it returns may or may not capture variables
   // that are given to the user-defined function.
   // Some examples are given in this file and are also useful
diff --git a/packages/seacas/libraries/ioss/src/init/Ionit_Initializer.C b/packages/seacas/libraries/ioss/src/init/Ionit_Initializer.C
index 9018a7af82aa..47be56adea03 100644
--- a/packages/seacas/libraries/ioss/src/init/Ionit_Initializer.C
+++ b/packages/seacas/libraries/ioss/src/init/Ionit_Initializer.C
@@ -1,4 +1,4 @@
-// Copyright(C) 1999-2020, 2023 National Technology & Engineering Solutions
+// Copyright(C) 1999-2020, 2023, 2024 National Technology & Engineering Solutions
 // of Sandia, LLC (NTESS).  Under the terms of Contract DE-NA0003525 with
 // NTESS, the U.S. Government retains certain rights in this software.
 //
@@ -10,8 +10,10 @@
 
 #if defined(SEACAS_HAVE_EXODUS)
 #include "exodus/Ioex_IOFactory.h"
+#if defined(SEACAS_HAVE_EXONULL)
 #include "exonull/Ioexnl_IOFactory.h"
 #endif
+#endif
 
 #include "gen_struc/Iogs_DatabaseIO.h"
 #include "generated/Iogn_DatabaseIO.h"
@@ -47,6 +49,8 @@
 
 #include "Ioss_IOFactory.h"
 
+#include "Ioss_DynamicTopology.h"
+
 namespace {
 #if defined(IOSS_THREADSAFE)
   std::mutex m_;
@@ -72,8 +76,10 @@ namespace Ioss::Init {
 
 #if defined(SEACAS_HAVE_EXODUS)
     Ioex::IOFactory::factory(); // Exodus
+#if defined(SEACAS_HAVE_EXONULL)
     Ioexnl::IOFactory::factory();
 #endif
+#endif
 #if defined(SEACAS_HAVE_PAMGEN)
     Iopg::IOFactory::factory(); // Pamgen
 #endif
@@ -94,6 +100,7 @@ namespace Ioss::Init {
     Iogs::IOFactory::factory(); // Structured Mesh Generator
     Ionull::IOFactory::factory();
     Ioss::StorageInitializer();
+    Ioss::DynamicTopologyBroker::broker();
     Ioss::Initializer();
     Iotr::Initializer();
 #ifdef HAVE_SEACASIOSS_ADIOS2
diff --git a/packages/seacas/libraries/ioss/src/main/io_info.C b/packages/seacas/libraries/ioss/src/main/io_info.C
index 1483423816ee..c8f25eaf6094 100644
--- a/packages/seacas/libraries/ioss/src/main/io_info.C
+++ b/packages/seacas/libraries/ioss/src/main/io_info.C
@@ -317,7 +317,11 @@ namespace {
       if (!sb->m_zoneConnectivity.empty()) {
         fmt::print("\tConnectivity with other blocks:\n");
         for (const auto &zgc : sb->m_zoneConnectivity) {
+#if defined __NVCC__
           std::cout << zgc << "\n";
+#else
+          fmt::print("{}\n", zgc);
+#endif
         }
       }
       if (!sb->m_boundaryConditions.empty()) {
@@ -331,7 +335,11 @@ namespace {
                    });
 
         for (const auto &bc : sb_bc) {
+#if defined __NVCC__
           std::cout << bc << "\n";
+#else
+          fmt::print("{}\n", bc);
+#endif
         }
       }
       if (interFace.compute_bbox()) {
diff --git a/packages/seacas/libraries/ioss/src/main/shell_interface.C b/packages/seacas/libraries/ioss/src/main/shell_interface.C
index 1bd000384359..40fad4c4e6b3 100644
--- a/packages/seacas/libraries/ioss/src/main/shell_interface.C
+++ b/packages/seacas/libraries/ioss/src/main/shell_interface.C
@@ -48,6 +48,9 @@ void IOShell::Interface::enroll_options()
                   "Database type for output file:"
 #if defined(SEACAS_HAVE_EXODUS)
                   " exodus"
+#if defined(SEACAS_HAVE_EXONULL)
+                  " exonull"
+#endif
 #endif
 #if defined(SEACAS_HAVE_CGNS)
                   " cgns"
@@ -55,7 +58,7 @@ void IOShell::Interface::enroll_options()
 #if defined(SEACAS_HAVE_FAODEL)
                   " faodel"
 #endif
-                  ".\n\t\tIf not specified, guess from extension or exodus is the default.",
+                  " null.\n\t\tIf not specified, guess from extension or exodus is the default.",
                   "unknown");
   options_.enroll("compare", Ioss::GetLongOption::NoValue,
                   "Compare the contents of the INPUT and OUTPUT files.", nullptr);
@@ -215,10 +218,10 @@ void IOShell::Interface::enroll_options()
                   "Files are decomposed externally into a file-per-processor in a parallel run.",
                   nullptr);
 
-  options_.enroll(
-      "add_processor_id_field", Ioss::GetLongOption::NoValue,
-      "Add a cell-centered field whose value is the processor id of that cell", nullptr);
-  
+  options_.enroll("add_processor_id_field", Ioss::GetLongOption::NoValue,
+                  "Add a cell-centered field whose value is the processor id of that cell",
+                  nullptr);
+
   options_.enroll("serialize_io_size", Ioss::GetLongOption::MandatoryValue,
                   "Number of processors that can perform simultaneous IO operations in "
                   "a parallel run;\n\t\t0 to disable",
@@ -233,10 +236,11 @@ void IOShell::Interface::enroll_options()
       "If non-zero, then put <$val> timesteps in each file. Then close file and start new file.",
       nullptr);
 
-  options_.enroll("split_cyclic", Ioss::GetLongOption::MandatoryValue,
-                  "If non-zero, then the `split_times` timesteps will be put into <$val> files\n\t\tand "
-                  "then recycle filenames.",
-                  nullptr);
+  options_.enroll(
+      "split_cyclic", Ioss::GetLongOption::MandatoryValue,
+      "If non-zero, then the `split_times` timesteps will be put into <$val> files\n\t\tand "
+      "then recycle filenames.",
+      nullptr);
 
   options_.enroll("file_per_state", Ioss::GetLongOption::NoValue,
                   "put transient data for each timestep in separate file (EXPERIMENTAL)", nullptr);
@@ -320,7 +324,7 @@ void IOShell::Interface::enroll_options()
 
   options_.enroll("omit_sets", Ioss::GetLongOption::MandatoryValue,
                   "comma-separated list of nodeset/edgeset/faceset/elemset/sideset names\n"
-		  "\t\tthat should NOT be transferred to output database",
+                  "\t\tthat should NOT be transferred to output database",
                   nullptr);
 
   options_.enroll("boundary_sideset", Ioss::GetLongOption::NoValue,
@@ -560,7 +564,7 @@ bool IOShell::Interface::parse_options(int argc, char **argv, int my_processor)
   }
 
   if (options_.retrieve("line_decomp") != nullptr) {
-    line_decomp = true;
+    line_decomp  = true;
     decomp_extra = options_.get_option_value("line_decomp", decomp_extra);
   }
 
diff --git a/packages/seacas/libraries/ioss/src/main/skinner.C b/packages/seacas/libraries/ioss/src/main/skinner.C
index 6ab0a4f0bc03..bda07b2181c2 100644
--- a/packages/seacas/libraries/ioss/src/main/skinner.C
+++ b/packages/seacas/libraries/ioss/src/main/skinner.C
@@ -230,7 +230,7 @@ namespace {
       auto              &boundary = boundary_faces[name];
       auto              &faces    = face_generator.faces(name);
       for (auto &face : faces) {
-        if (face.elementCount_ == 1) {
+        if (face.element_count() == 1) {
           boundary.push_back(face);
         }
       }
diff --git a/packages/seacas/libraries/ioss/src/main/sphgen.C b/packages/seacas/libraries/ioss/src/main/sphgen.C
index b41d5b98320d..054e6e2823c8 100644
--- a/packages/seacas/libraries/ioss/src/main/sphgen.C
+++ b/packages/seacas/libraries/ioss/src/main/sphgen.C
@@ -1,4 +1,4 @@
-// Copyright(C) 1999-2023 National Technology & Engineering Solutions
+// Copyright(C) 1999-2024 National Technology & Engineering Solutions
 // of Sandia, LLC (NTESS).  Under the terms of Contract DE-NA0003525 with
 // NTESS, the U.S. Government retains certain rights in this software.
 //
@@ -232,12 +232,12 @@ namespace {
       Ioss::ElementBlock *eb = *I;
       ++I;
       std::string type = eb->topology()->name();
+      std::string name = eb->name();
       if (type == Ioss::Hex8::name) {
         sph_node_count += eb->entity_count();
 
         // Add the element block...
-        int         num_elem = eb->entity_count();
-        std::string name     = eb->name();
+        int   num_elem = eb->entity_count();
         auto *ebn = new Ioss::ElementBlock(output_region.get_database(), name, "sphere", num_elem);
         int   id  = eb->get_property("id").get_int();
         ebn->property_add(Ioss::Property("id", id));
@@ -253,6 +253,9 @@ namespace {
         ns->property_add(Ioss::Property("id", id));
         output_region.add(ns);
       }
+      else {
+        fmt::print("Skipping block {} which contains {} elements.\n", name, type);
+      }
     }
 
     // Define a node block...
diff --git a/packages/seacas/libraries/ioss/src/text_mesh/Iotm_TextMesh.C b/packages/seacas/libraries/ioss/src/text_mesh/Iotm_TextMesh.C
index 270b20da68c0..51d6490033a8 100644
--- a/packages/seacas/libraries/ioss/src/text_mesh/Iotm_TextMesh.C
+++ b/packages/seacas/libraries/ioss/src/text_mesh/Iotm_TextMesh.C
@@ -938,6 +938,7 @@ namespace Iotm {
 
       for (const std::string &assemblyName : m_data.assemblies.get_part_names()) {
         const AssemblyData *assembly = m_data.assemblies.get_group_data(assemblyName);
+        ThrowRequireMsg(nullptr != assembly, "Could not find assembly with name" << assemblyName);
 
         bool omitAssembly =
             std::binary_search(assemblyOmissions.begin(), assemblyOmissions.end(), assembly->name);
diff --git a/packages/seacas/libraries/ioss/src/unit_tests/CMakeLists.txt b/packages/seacas/libraries/ioss/src/unit_tests/CMakeLists.txt
index 17a7bbb4403e..db5ff09522f7 100644
--- a/packages/seacas/libraries/ioss/src/unit_tests/CMakeLists.txt
+++ b/packages/seacas/libraries/ioss/src/unit_tests/CMakeLists.txt
@@ -14,6 +14,17 @@ TRIBITS_ADD_EXECUTABLE(
  SOURCES unitMain.C UnitTestElementBlockBatchRead.C
 )
 
+TRIBITS_ADD_EXECUTABLE(
+ Utst_dynamictopology
+ SOURCES unitMain.C UnitTestDynamicTopology.C
+)
+
+TRIBITS_ADD_TEST(
+        Utst_dynamictopology
+        NAME Utst_dynamictopology
+        NUM_MPI_PROCS 1
+)
+
 TRIBITS_ADD_TEST(
         Utst_blockbatchread
         NAME Utst_blockbatchread
diff --git a/packages/seacas/libraries/ioss/src/unit_tests/UnitTestDynamicTopology.C b/packages/seacas/libraries/ioss/src/unit_tests/UnitTestDynamicTopology.C
new file mode 100644
index 000000000000..b42cc43027d1
--- /dev/null
+++ b/packages/seacas/libraries/ioss/src/unit_tests/UnitTestDynamicTopology.C
@@ -0,0 +1,1111 @@
+// Copyright(C) 2024 National Technology & Engineering Solutions
+// of Sandia, LLC (NTESS).  Under the terms of Contract DE-NA0003525 with
+// NTESS, the U.S. Government retains certain rights in this software.
+//
+// See packages/seacas/LICENSE for details
+
+#include <string>
+#include <vector>
+
+#ifdef SEACAS_HAVE_MPI
+#include "mpi.h"
+#endif
+#include "gtest/gtest.h"
+
+#include <algorithm>
+#include <fstream>
+#include <functional>
+#include <iostream>
+#include <random>
+
+#include <unistd.h> // for unlink
+
+#include "Ionit_Initializer.h"
+#include "Ioss_DatabaseIO.h" // for DatabaseIO
+#include "Ioss_DBUsage.h"
+#include "Ioss_ElementBlock.h"
+#include "Ioss_Field.h"      // for Field, etc
+#include "Ioss_FileInfo.h"
+#include "Ioss_IOFactory.h"
+#include "Ioss_NodeBlock.h"
+#include "Ioss_ParallelUtils.h"
+#include "Ioss_Property.h"
+#include "Ioss_Region.h"
+#include "Ioss_Utils.h"
+
+#include "exodus/Ioex_DatabaseIO.h"
+
+namespace {
+std::string get_many_block_mesh_desc(unsigned numBlocks)
+{
+  std::ostringstream    oss;
+  std::vector<unsigned> elementIds(numBlocks);
+  std::iota(elementIds.begin(), elementIds.end(), 1);
+
+  unsigned proc = 0;
+  for (unsigned i = 0; i < numBlocks; ++i) {
+    unsigned elemId      = elementIds[i];
+    unsigned firstNodeId = i * 4 + 1;
+    oss << proc << "," << elemId << ",HEX_8,";
+    for (unsigned node = firstNodeId; node < firstNodeId + 8; ++node) {
+      oss << node << ",";
+    }
+    unsigned blockId = i + 1;
+    oss << "block_" << blockId;
+
+    if (i < numBlocks - 1) {
+      oss << "\n";
+    }
+
+    proc++;
+  }
+
+  oss << "|coordinates:";
+
+  std::vector<double> planeCoords = {0, 0, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0};
+
+  for (double coord : planeCoords) {
+    oss << coord << ",";
+  }
+
+  for (unsigned i = 1; i <= numBlocks; ++i) {
+    for (unsigned point = 0; point < 4; ++point) {
+      planeCoords[3 * point + 2] += 1;
+    }
+
+    for (double coord : planeCoords) {
+      oss << coord << ",";
+    }
+  }
+
+  return oss.str();
+}
+
+void define_model(const Ioss::Region &i_region, Ioss::Region &o_region)
+{
+  Ioss::DatabaseIO *o_database = o_region.get_database();
+
+  o_region.begin_mode(Ioss::STATE_DEFINE_MODEL);
+
+  auto& nodeblocks = o_region.get_node_blocks();
+
+  Ioss::NodeBlock *i_nb        = i_region.get_node_blocks()[0];
+  int64_t          spatial_dim = 3;
+  int64_t          num_nodes   = i_nb->entity_count();
+  Ioss::NodeBlock *o_nb = new Ioss::NodeBlock(o_database, "nodeblock_1", num_nodes, spatial_dim);
+  o_region.add(o_nb);
+
+  for (Ioss::ElementBlock *i_eb : i_region.get_element_blocks()) {
+    Ioss::ElementBlock *o_eb = new Ioss::ElementBlock(
+        o_database, i_eb->name(), i_eb->topology()->name(), i_eb->entity_count());
+    o_eb->property_add(i_eb->get_property("id"));
+    o_region.add(o_eb);
+  }
+
+  o_region.end_mode(Ioss::STATE_DEFINE_MODEL);
+}
+
+void write_model(const Ioss::Region &i_region, Ioss::Region &o_region)
+{
+  Ioss::NodeBlock *i_nb = i_region.get_node_blocks()[0];
+  Ioss::NodeBlock *o_nb = o_region.get_node_blocks()[0];
+
+  o_region.begin_mode(Ioss::STATE_MODEL);
+  std::vector<double> coordinates;
+  std::vector<int>    node_ids;
+  i_nb->get_field_data("ids", node_ids);
+  i_nb->get_field_data("mesh_model_coordinates", coordinates);
+
+  o_nb->put_field_data("ids", node_ids);
+  o_nb->put_field_data("mesh_model_coordinates", coordinates);
+
+  for (Ioss::ElementBlock *i_eb : i_region.get_element_blocks()) {
+    Ioss::ElementBlock *o_eb = o_region.get_element_block(i_eb->name());
+    std::vector<int>    elem_ids;
+    std::vector<int>    connectivity;
+
+    i_eb->get_field_data("ids", elem_ids);
+    i_eb->get_field_data("connectivity", connectivity);
+
+    o_eb->put_field_data("ids", elem_ids);
+    o_eb->put_field_data("connectivity", connectivity);
+  }
+
+  o_region.end_mode(Ioss::STATE_MODEL);
+}
+
+void define_transient(const Ioss::Region &i_region, Ioss::Region &o_region,
+                      const std::string &elemFieldName)
+{
+  o_region.begin_mode(Ioss::STATE_DEFINE_TRANSIENT);
+
+  for (Ioss::ElementBlock *o_eb : o_region.get_element_blocks()) {
+    size_t      num_elem = o_eb->get_property("entity_count").get_int();
+    std::string storage  = "scalar";
+
+    Ioss::Field field(elemFieldName, Ioss::Field::REAL, storage, 1, Ioss::Field::Field::TRANSIENT,
+                      num_elem);
+    o_eb->field_add(field);
+  }
+  o_region.end_mode(Ioss::STATE_DEFINE_TRANSIENT);
+}
+
+int write_transient(Ioss::Region &o_region, const std::string &elemFieldName, const double time)
+{
+  o_region.begin_mode(Ioss::STATE_TRANSIENT);
+  int step = o_region.add_state(time);
+  o_region.begin_state(step);
+
+  for (Ioss::ElementBlock *o_eb : o_region.get_element_blocks()) {
+    size_t num_elem = o_eb->get_property("entity_count").get_int();
+
+    std::vector<double> field_data(num_elem);
+    std::vector<int>    elem_ids;
+
+    o_eb->get_field_data("ids", elem_ids);
+    for (size_t i = 0; i < elem_ids.size(); i++) {
+      field_data[i] = (double)elem_ids[i] + 100*time;
+    }
+
+    o_eb->put_field_data(elemFieldName, field_data);
+  }
+
+  o_region.end_state(step);
+  o_region.end_mode(Ioss::STATE_TRANSIENT);
+
+  return step;
+}
+
+class Observer : public Ioss::DynamicTopologyObserver
+{
+public:
+  Observer(Ioss::Region& inputRegion_,
+           const std::string &elemFieldName_,
+           const Ioss::FileControlOption fileControlOption_)
+  : Ioss::DynamicTopologyObserver(nullptr)
+  , inputRegion(inputRegion_)
+  , elemFieldName(elemFieldName_)
+  , fileControlOption(fileControlOption_)
+  {}
+
+  virtual ~Observer() {}
+
+  void define_model() override
+  {
+    ::define_model(inputRegion, *get_region());
+  }
+
+  void write_model() override
+  {
+    ::write_model(inputRegion, *get_region());
+  }
+
+  void define_transient() override
+  {
+    ::define_transient(inputRegion, *get_region(), elemFieldName);
+  }
+
+  Ioss::FileControlOption get_control_option() const
+  {
+    return fileControlOption;
+  }
+
+private:
+  Observer();
+
+  Ioss::Region& inputRegion;
+  const std::string elemFieldName;
+  Ioss::FileControlOption fileControlOption;
+};
+
+struct OutputParams {
+  OutputParams(const std::string& outFile_)
+  : outFile(outFile_) {}
+
+  OutputParams(const std::string& outFile_, const std::string& elemFieldName_)
+  : outFile(outFile_)
+  , elemFieldName(elemFieldName_) {}
+
+  void set_data(const std::vector<double>& output_times_,
+                const std::vector<bool>&   output_steps_,
+                const std::vector<bool>&   modification_steps_)
+  {
+    ASSERT_EQ(output_times_.size(), output_steps_.size());
+    ASSERT_EQ(output_times_.size(), modification_steps_.size());
+
+    size_t numSteps = output_times_.size();
+    for(auto i=1; i<numSteps; i++) {
+      // Monotone increasing
+      ASSERT_TRUE(output_times_[i] > output_times_[i-1]);
+    }
+
+    output_times = output_times_;
+    output_steps = output_steps_;
+    modification_steps = modification_steps_;
+  }
+
+  void set_data(const std::vector<bool>&   output_steps_,
+                const std::vector<bool>&   modification_steps_)
+  {
+    ASSERT_EQ(output_steps_.size(), modification_steps_.size());
+
+    size_t numSteps = output_steps_.size();
+    for(size_t i=0; i<numSteps; i++) {
+      output_times.push_back((double)i);
+    }
+    output_steps = output_steps_;
+    modification_steps = modification_steps_;
+  }
+
+  struct OutputParams& add(const double time, const bool do_output, const bool do_modification)
+  {
+    size_t numSteps = output_times.size();
+    if(numSteps > 0) {
+      // Monotone increasing
+      EXPECT_TRUE(time > output_times[numSteps-1]);
+    }
+
+    output_times.push_back(time);
+    output_steps.push_back(do_output);
+    modification_steps.push_back(do_modification);
+
+    return *this;
+  }
+
+  void clear()
+  {
+    output_times.clear();
+    output_steps.clear();
+    modification_steps.clear();
+  }
+
+  std::string outFile{"file.g"};
+  std::string elemFieldName{"elem_field"};
+  std::vector<double> output_times;
+  std::vector<bool>   output_steps;
+  std::vector<bool>   modification_steps;
+};
+
+void do_output(Ioss::Region &o_region,
+               const OutputParams& params,
+               size_t step,
+               double& minTime,
+               int& maxStep,
+               bool& doneOutputAfterModification)
+{
+  if(params.output_steps[step]) {
+    if(!doneOutputAfterModification) {
+      minTime = params.output_times[step];
+    }
+
+    write_transient(o_region, params.elemFieldName, params.output_times[step]);
+
+    auto min_result = o_region.get_min_time();
+    EXPECT_EQ(1, min_result.first);
+    EXPECT_NEAR(minTime, min_result.second, 1.0e-6);
+
+    auto max_result = o_region.get_max_time();
+    EXPECT_EQ(maxStep, max_result.first);
+    EXPECT_NEAR(params.output_times[step], max_result.second, 1.0e-6);
+
+    maxStep++;
+    doneOutputAfterModification = true;
+  }
+}
+
+void run_topology_change(const Ioss::Region& i_region,
+                         Ioss::Region &o_region,
+                         const OutputParams& params)
+{
+  auto observer = o_region.get_mesh_modification_observer();
+
+  define_model(i_region, o_region);
+  write_model(i_region, o_region);
+
+  define_transient(i_region, o_region, params.elemFieldName);
+
+  auto numSteps = params.output_steps.size();
+
+  int maxStep = 1;
+
+  double minTime = numSteps > 0 ? params.output_times[0] : 0.0;
+  double maxTime = numSteps > 0 ? params.output_times[0] : 0.0;
+
+  bool doneOutputAfterModification = true;
+
+  for(size_t i=0; i<numSteps; i++)
+  {
+    if(params.modification_steps[i]) {
+      observer->set_topology_modification(Ioss::TOPOLOGY_UNKNOWN);
+      maxStep = 1;
+      doneOutputAfterModification = false;
+    }
+
+    do_output(o_region, params, i, minTime, maxStep, doneOutputAfterModification);
+  }
+}
+
+void cleanup_simple_multi_files(const std::string &outFile)
+{
+  Ioss::ParallelUtils util(Ioss::ParallelUtils::comm_world());
+
+  std::string file1 = Ioss::Utils::decode_filename(outFile, util.parallel_rank(), util.parallel_size());
+  unlink(file1.c_str());
+
+  std::string file2 = Ioss::Utils::decode_filename(outFile + "-s0002", util.parallel_rank(), util.parallel_size());
+  unlink(file2.c_str());
+
+  std::string file3 = Ioss::Utils::decode_filename(outFile + "-s0003", util.parallel_rank(), util.parallel_size());
+  unlink(file3.c_str());
+
+  std::string file4 = Ioss::Utils::decode_filename(outFile + "-s0004", util.parallel_rank(), util.parallel_size());
+  unlink(file4.c_str());
+}
+
+void run_multi_file_simple_topology_change(const OutputParams& params)
+{
+  Ioss::Init::Initializer io;
+  Ioss::ParallelUtils util(Ioss::ParallelUtils::comm_world());
+
+  int numBlocks = util.parallel_size();
+
+  std::string meshDesc = get_many_block_mesh_desc(numBlocks);
+
+  Ioss::PropertyManager propertyManager;
+
+  Ioss::DatabaseIO *i_database = Ioss::IOFactory::create("textmesh", meshDesc, Ioss::READ_MODEL,
+                                                         Ioss::ParallelUtils::comm_world(),
+                                                         propertyManager);
+  Ioss::Region i_region(i_database, "input_model");
+  EXPECT_TRUE(i_database != nullptr);
+  EXPECT_TRUE(i_database->ok(true));
+
+  Ioss::DatabaseIO *o_database = Ioss::IOFactory::create("exodus", params.outFile, Ioss::WRITE_RESULTS,
+                                                         Ioss::ParallelUtils::comm_world(),
+                                                         propertyManager);
+  Ioss::Region o_region(o_database, "output_model");
+  EXPECT_TRUE(o_database != nullptr);
+  EXPECT_TRUE(o_database->ok(true));
+
+  auto fileControlOption = Ioss::FileControlOption::CONTROL_AUTO_MULTI_FILE;
+  auto observer = std::make_shared<Observer>(i_region, params.elemFieldName, fileControlOption);
+  o_region.register_mesh_modification_observer(observer);
+
+  run_topology_change(i_region, o_region, params);
+}
+
+TEST(TestDynamicWrite, multi_file_simple_topology_modification)
+{
+  std::string outFile("multiFileManyBlocks.g");
+  std::string elemFieldName = "elem_field";
+
+  OutputParams params(outFile, elemFieldName);
+
+  std::vector<bool>       output_steps{true , true, true,  true, true, true};
+  std::vector<bool> modification_steps{false, true, false, true, true, false};
+
+  params.set_data(output_steps, modification_steps);
+
+  cleanup_simple_multi_files(outFile);
+  run_multi_file_simple_topology_change(params);
+  cleanup_simple_multi_files(outFile);
+}
+
+void cleanup_cyclic_multi_files(const std::string &outFile)
+{
+  Ioss::ParallelUtils util(Ioss::ParallelUtils::comm_world());
+
+  std::string file1 = Ioss::Utils::decode_filename(outFile, util.parallel_rank(), util.parallel_size());
+  unlink(file1.c_str());
+
+  std::string file2 = Ioss::Utils::decode_filename(outFile + "-A", util.parallel_rank(), util.parallel_size());
+  unlink(file2.c_str());
+
+  std::string file3 = Ioss::Utils::decode_filename(outFile + "-B", util.parallel_rank(), util.parallel_size());
+  unlink(file3.c_str());
+
+  std::string file4 = Ioss::Utils::decode_filename(outFile + "-C", util.parallel_rank(), util.parallel_size());
+  unlink(file4.c_str());
+}
+
+void run_multi_file_cyclic_topology_change(const OutputParams& params)
+{
+  Ioss::Init::Initializer io;
+  Ioss::ParallelUtils util(Ioss::ParallelUtils::comm_world());
+
+  int numBlocks = util.parallel_size();
+
+  std::string meshDesc = get_many_block_mesh_desc(numBlocks);
+
+  Ioss::PropertyManager propertyManager;
+
+  Ioss::DatabaseIO *i_database = Ioss::IOFactory::create("textmesh", meshDesc, Ioss::READ_MODEL,
+                                                         Ioss::ParallelUtils::comm_world(),
+                                                         propertyManager);
+  Ioss::Region i_region(i_database, "input_model");
+  EXPECT_TRUE(i_database != nullptr);
+  EXPECT_TRUE(i_database->ok(true));
+
+  Ioss::DatabaseIO *o_database = Ioss::IOFactory::create("exodus", params.outFile, Ioss::WRITE_RESULTS,
+                                                         Ioss::ParallelUtils::comm_world(),
+                                                         propertyManager);
+  Ioss::Region o_region(o_database, "output_model");
+  EXPECT_TRUE(o_database != nullptr);
+  EXPECT_TRUE(o_database->ok(true));
+
+  auto fileControlOption = Ioss::FileControlOption::CONTROL_AUTO_MULTI_FILE;
+  auto observer = std::make_shared<Observer>(i_region, params.elemFieldName, fileControlOption);
+  o_region.register_mesh_modification_observer(observer);
+
+  o_region.set_file_cyclic_count(3);
+  run_topology_change(i_region, o_region, params);
+}
+
+TEST(TestDynamicWrite, multi_file_cyclic_topology_modification)
+{
+  std::string outFile("cyclicMultiFileManyBlocks.g");
+  std::string elemFieldName = "elem_field";
+
+  OutputParams params(outFile, elemFieldName);
+
+  std::vector<double>        output_times{0.0  , 0.5 , 1.5  , 1.75, 2.0 ,   3.0};
+  std::vector<bool>          output_steps{true , true, true , true, true, true };
+  std::vector<bool>    modification_steps{false, true, false, true, true, false};
+
+  params.set_data(output_times, output_steps, modification_steps);
+
+  cleanup_cyclic_multi_files(outFile);
+  run_multi_file_cyclic_topology_change(params);
+  cleanup_cyclic_multi_files(outFile);
+}
+
+void fill_group_gold_names(const int numFileGroups,
+                           std::vector<std::string>& gold_names,
+                           std::vector<std::string>& gold_full_names)
+{
+  gold_names.clear();
+  gold_full_names.clear();
+
+  gold_names.push_back("/");
+  gold_full_names.push_back("/");
+
+  for(int i=1; i<=numFileGroups; i++) {
+    std::ostringstream oss;
+    oss << Ioss::DynamicTopologyFileControl::group_prefix();
+    oss << i;
+
+    gold_names.push_back(oss.str());
+    gold_full_names.push_back("/" + oss.str());
+  }
+}
+
+void test_group_names(Ioss::DatabaseIO *database)
+{
+  Ioss::NameList names = database->groups_describe(false);
+  Ioss::NameList full_names = database->groups_describe(true);
+
+  std::vector<std::string> gold_names;
+  std::vector<std::string> gold_full_names;
+
+  fill_group_gold_names(database->num_child_group(), gold_names, gold_full_names);
+
+  EXPECT_EQ(gold_names, names);
+  EXPECT_EQ(gold_full_names, full_names);
+}
+
+void cleanup_single_file(const std::string &outFile)
+{
+  Ioss::ParallelUtils util(Ioss::ParallelUtils::comm_world());
+
+  std::string file1 = Ioss::Utils::decode_filename(outFile, util.parallel_rank(), util.parallel_size());
+  unlink(file1.c_str());
+}
+
+void run_single_file_simple_topology_change(const OutputParams& params)
+{
+  Ioss::Init::Initializer io;
+  Ioss::ParallelUtils util(Ioss::ParallelUtils::comm_world());
+
+  int numBlocks = util.parallel_size();
+
+  std::string meshDesc = get_many_block_mesh_desc(numBlocks);
+
+  Ioss::PropertyManager propertyManager;
+
+  Ioss::DatabaseIO *i_database = Ioss::IOFactory::create("textmesh", meshDesc, Ioss::READ_MODEL,
+                                                         Ioss::ParallelUtils::comm_world(),
+                                                         propertyManager);
+  Ioss::Region i_region(i_database, "input_model");
+  EXPECT_TRUE(i_database != nullptr);
+  EXPECT_TRUE(i_database->ok(true));
+
+  propertyManager.add(Ioss::Property("ENABLE_FILE_GROUPS", 1));
+  propertyManager.add(Ioss::Property("APPEND_OUTPUT", Ioss::DB_APPEND_GROUP));
+  Ioss::DatabaseIO *o_database = Ioss::IOFactory::create("exodus", params.outFile, Ioss::WRITE_RESULTS,
+                                                         Ioss::ParallelUtils::comm_world(),
+                                                         propertyManager);
+  Ioss::Region o_region(o_database, "output_model");
+  EXPECT_TRUE(o_database != nullptr);
+  EXPECT_TRUE(o_database->ok(true));
+
+  auto fileControlOption = Ioss::FileControlOption::CONTROL_AUTO_GROUP_FILE;
+  auto observer = std::make_shared<Observer>(i_region, params.elemFieldName, fileControlOption);
+  o_region.register_mesh_modification_observer(observer);
+
+  run_topology_change(i_region, o_region, params);
+  test_group_names(o_database);
+}
+
+TEST(TestDynamicWrite, single_file_simple_topology_modification)
+{
+  std::string outFile("singleFileManyBlocks.g");
+  std::string elemFieldName = "elem_field";
+
+  OutputParams params(outFile, elemFieldName);
+
+  params.add(0.0, true, false)
+        .add(1.0, true, true)
+        .add(2.0, true, false)
+        .add(3.0, true, true)
+        .add(4.0, true, true)
+        .add(5.0, true, false);
+
+  cleanup_single_file(outFile);
+  run_single_file_simple_topology_change(params);
+  cleanup_single_file(outFile);
+}
+
+TEST(TestDynamicWrite, single_file_groups_not_enabled)
+{
+  Ioss::Init::Initializer io;
+  Ioss::ParallelUtils util(Ioss::ParallelUtils::comm_world());
+
+  int numBlocks = util.parallel_size();
+  if(numBlocks > 1) GTEST_SKIP();
+
+  std::string meshDesc = "0,1,HEX_8,1,2,3,4,5,6,7,8,block_1"
+                         "|coordinates:0,0,0,1,0,0,1,1,0,0,1,0,0,0,1,1,0,1,1,1,1,0,1,1";
+
+  Ioss::PropertyManager propertyManager;
+
+  Ioss::DatabaseIO *i_database = Ioss::IOFactory::create("textmesh", meshDesc, Ioss::READ_MODEL,
+                                                         Ioss::ParallelUtils::comm_world(),
+                                                         propertyManager);
+  Ioss::Region i_region(i_database, "input_model");
+  EXPECT_TRUE(i_database != nullptr);
+  EXPECT_TRUE(i_database->ok(true));
+
+  std::string outFile("singleFileGroupsNotEnabled.g");
+  std::string elemFieldName = "elem_field";
+  cleanup_single_file(outFile);
+
+  // Need the line below to allow this to pass
+  // propertyManager.add(Ioss::Property("ENABLE_FILE_GROUPS", 1));
+  propertyManager.add(Ioss::Property("APPEND_OUTPUT", Ioss::DB_APPEND_GROUP));
+  Ioss::DatabaseIO *o_database = Ioss::IOFactory::create("exodus", outFile, Ioss::WRITE_RESULTS,
+                                                         Ioss::ParallelUtils::comm_world(),
+                                                         propertyManager);
+  Ioss::Region o_region(o_database, "output_model");
+  EXPECT_TRUE(o_database != nullptr);
+  EXPECT_TRUE(o_database->ok(true));
+
+  auto fileControlOption = Ioss::FileControlOption::CONTROL_AUTO_GROUP_FILE;
+  auto observer = std::make_shared<Observer>(i_region, elemFieldName, fileControlOption);
+  EXPECT_THROW(o_region.register_mesh_modification_observer(observer), std::runtime_error);
+  cleanup_single_file(outFile);
+}
+
+TEST(TestDynamicWrite, create_subgroup_with_file_reopen)
+{
+  std::string outFile("subgroupManyBlocks.g");
+  std::string elemFieldName = "elem_field";
+
+  Ioss::Init::Initializer io;
+  Ioss::ParallelUtils util(Ioss::ParallelUtils::comm_world());
+
+  std::string file1 = Ioss::Utils::decode_filename(outFile, util.parallel_rank(), util.parallel_size());
+  unlink(file1.c_str());
+
+  int numBlocks = util.parallel_size();
+  if(numBlocks > 1) GTEST_SKIP();
+
+  std::string meshDesc = "0,1,HEX_8,1,2,3,4,5,6,7,8,block_1"
+                         "|coordinates:0,0,0,1,0,0,1,1,0,0,1,0,0,0,1,1,0,1,1,1,1,0,1,1";
+
+  Ioss::PropertyManager propertyManager;
+
+  Ioss::DatabaseIO *i_database = Ioss::IOFactory::create("textmesh", meshDesc, Ioss::READ_MODEL,
+                                                         Ioss::ParallelUtils::comm_world(),
+                                                         propertyManager);
+  Ioss::Region i_region(i_database, "input_model");
+  EXPECT_TRUE(i_database != nullptr);
+  EXPECT_TRUE(i_database->ok(true));
+
+  {
+    propertyManager.add(Ioss::Property("ENABLE_FILE_GROUPS", 1));
+    Ioss::DatabaseIO *o_database = Ioss::IOFactory::create("exodus", outFile, Ioss::WRITE_RESULTS,
+                                                           Ioss::ParallelUtils::comm_world(),
+                                                           propertyManager);
+    Ioss::Region o_region(o_database, "output_model");
+    EXPECT_TRUE(o_database != nullptr);
+    EXPECT_TRUE(o_database->ok(true));
+    o_database->create_subgroup("GROUP_1");
+  }
+
+  {
+    propertyManager.add(Ioss::Property("APPEND_OUTPUT", Ioss::DB_APPEND_GROUP));
+    Ioss::DatabaseIO *o_database = Ioss::IOFactory::create("exodus", outFile, Ioss::WRITE_RESULTS,
+                                                           Ioss::ParallelUtils::comm_world(),
+                                                           propertyManager);
+    Ioss::Region o_region(o_database, "output_model");
+    EXPECT_TRUE(o_database != nullptr);
+    EXPECT_TRUE(o_database->ok(true));
+
+    // Group pointer is automatically at first child
+    o_database->create_subgroup("GROUP_2");
+
+    Ioss::NameList names = o_database->groups_describe(false);
+    Ioss::NameList full_names = o_database->groups_describe(true);
+
+    std::vector<std::string> gold_names{"/", "GROUP_1", "GROUP_2"};
+    std::vector<std::string> gold_full_names{"/", "/GROUP_1", "/GROUP_1/GROUP_2"};
+
+    EXPECT_EQ(gold_names, names);
+    EXPECT_EQ(gold_full_names, full_names);
+  }
+
+  unlink(file1.c_str());
+}
+
+TEST(TestDynamicWrite, create_subgroup_with_file_persistence_and_child_group)
+{
+  std::string outFile("subgroupManyBlocks.g");
+  std::string elemFieldName = "elem_field";
+
+  Ioss::Init::Initializer io;
+  Ioss::ParallelUtils util(Ioss::ParallelUtils::comm_world());
+
+  std::string file1 = Ioss::Utils::decode_filename(outFile, util.parallel_rank(), util.parallel_size());
+  unlink(file1.c_str());
+
+  int numBlocks = util.parallel_size();
+  if(numBlocks > 1) GTEST_SKIP();
+
+  std::string meshDesc = "0,1,HEX_8,1,2,3,4,5,6,7,8,block_1"
+                         "|coordinates:0,0,0,1,0,0,1,1,0,0,1,0,0,0,1,1,0,1,1,1,1,0,1,1";
+
+  Ioss::PropertyManager propertyManager;
+
+  Ioss::DatabaseIO *i_database = Ioss::IOFactory::create("textmesh", meshDesc, Ioss::READ_MODEL,
+                                                         Ioss::ParallelUtils::comm_world(),
+                                                         propertyManager);
+  Ioss::Region i_region(i_database, "input_model");
+  EXPECT_TRUE(i_database != nullptr);
+  EXPECT_TRUE(i_database->ok(true));
+
+  {
+    propertyManager.add(Ioss::Property("ENABLE_FILE_GROUPS", 1));
+    propertyManager.add(Ioss::Property("APPEND_OUTPUT", Ioss::DB_APPEND_GROUP));
+    Ioss::DatabaseIO *o_database = Ioss::IOFactory::create("exodus", outFile, Ioss::WRITE_RESULTS,
+                                                           Ioss::ParallelUtils::comm_world(),
+                                                           propertyManager);
+    Ioss::Region o_region(o_database, "output_model");
+    EXPECT_TRUE(o_database != nullptr);
+    EXPECT_TRUE(o_database->ok(true));
+
+    o_database->create_subgroup("GROUP_1");
+
+    // Group pointer is at "GROUP_1" ... "GROUP_2" is a child
+    o_database->create_subgroup("GROUP_2");
+
+    Ioss::NameList names = o_database->groups_describe(false);
+    Ioss::NameList full_names = o_database->groups_describe(true);
+
+    std::vector<std::string> gold_names{"/", "GROUP_1", "GROUP_2"};
+    std::vector<std::string> gold_full_names{"/", "/GROUP_1", "/GROUP_1/GROUP_2"};
+
+    EXPECT_EQ(gold_names, names);
+    EXPECT_EQ(gold_full_names, full_names);
+  }
+
+  unlink(file1.c_str());
+}
+
+TEST(TestDynamicWrite, create_subgroup_with_file_persistence_and_no_child_group)
+{
+  std::string outFile("subgroupManyBlocks.g");
+  std::string elemFieldName = "elem_field";
+
+  Ioss::Init::Initializer io;
+  Ioss::ParallelUtils util(Ioss::ParallelUtils::comm_world());
+
+  std::string file1 = Ioss::Utils::decode_filename(outFile, util.parallel_rank(), util.parallel_size());
+  unlink(file1.c_str());
+
+  int numBlocks = util.parallel_size();
+  if(numBlocks > 1) GTEST_SKIP();
+
+  std::string meshDesc = "0,1,HEX_8,1,2,3,4,5,6,7,8,block_1"
+                         "|coordinates:0,0,0,1,0,0,1,1,0,0,1,0,0,0,1,1,0,1,1,1,1,0,1,1";
+
+  Ioss::PropertyManager propertyManager;
+
+  Ioss::DatabaseIO *i_database = Ioss::IOFactory::create("textmesh", meshDesc, Ioss::READ_MODEL,
+                                                         Ioss::ParallelUtils::comm_world(),
+                                                         propertyManager);
+  Ioss::Region i_region(i_database, "input_model");
+  EXPECT_TRUE(i_database != nullptr);
+  EXPECT_TRUE(i_database->ok(true));
+
+  {
+    propertyManager.add(Ioss::Property("ENABLE_FILE_GROUPS", 1));
+    propertyManager.add(Ioss::Property("APPEND_OUTPUT", Ioss::DB_APPEND_GROUP));
+    Ioss::DatabaseIO *o_database = Ioss::IOFactory::create("exodus", outFile, Ioss::WRITE_RESULTS,
+                                                           Ioss::ParallelUtils::comm_world(),
+                                                           propertyManager);
+    Ioss::Region o_region(o_database, "output_model");
+    EXPECT_TRUE(o_database != nullptr);
+    EXPECT_TRUE(o_database->ok(true));
+
+    o_database->create_subgroup("GROUP_1");
+
+    // Group pointer is reset to root group
+    EXPECT_TRUE(o_database->open_root_group());
+    o_database->create_subgroup("GROUP_2");
+
+    Ioss::NameList names = o_database->groups_describe(false);
+    Ioss::NameList full_names = o_database->groups_describe(true);
+
+    std::vector<std::string> gold_names{"/", "GROUP_1", "GROUP_2"};
+    std::vector<std::string> gold_full_names{"/", "/GROUP_1", "/GROUP_2"};
+
+    EXPECT_EQ(gold_names, names);
+    EXPECT_EQ(gold_full_names, full_names);
+  }
+
+  unlink(file1.c_str());
+}
+
+
+void run_topology_change_with_multiple_output(const Ioss::Region& i_region,
+                                              Ioss::Region &o_region1,
+                                              Ioss::Region &o_region2,
+                                              const OutputParams& params1,
+                                              const OutputParams& params2)
+{
+  ASSERT_EQ(params1.modification_steps, params2.modification_steps);
+
+  auto observer1 = o_region1.get_mesh_modification_observer();
+  auto observer2 = o_region2.get_mesh_modification_observer();
+
+  define_model(i_region, o_region1);
+  write_model(i_region, o_region1);
+  define_transient(i_region, o_region1, params1.elemFieldName);
+
+  define_model(i_region, o_region2);
+  write_model(i_region, o_region2);
+  define_transient(i_region, o_region2, params2.elemFieldName);
+
+  auto numSteps = params1.output_steps.size();
+
+  int maxStep1 = 1;
+  int maxStep2 = 1;
+
+  double minTime1 = numSteps > 0 ? params1.output_times[0] : 0.0;
+  double minTime2 = numSteps > 0 ? params2.output_times[0] : 0.0;
+
+  bool doneOutputAfterModification1 = true;
+  bool doneOutputAfterModification2 = true;
+
+  for(size_t i=0; i<numSteps; i++)
+  {
+    if(params1.modification_steps[i]) {
+      EXPECT_TRUE(params2.modification_steps[i]);
+
+      observer1->set_topology_modification(Ioss::TOPOLOGY_UNKNOWN);
+      maxStep1 = 1;
+      maxStep2 = 1;
+
+      EXPECT_EQ(Ioss::TOPOLOGY_UNKNOWN, observer1->get_topology_modification());
+      EXPECT_EQ(Ioss::TOPOLOGY_UNKNOWN, observer2->get_topology_modification());
+
+      doneOutputAfterModification1 = false;
+      doneOutputAfterModification2 = false;
+    }
+
+    do_output(o_region1, params1, i, minTime1, maxStep1, doneOutputAfterModification1);
+    do_output(o_region2, params2, i, minTime2, maxStep2, doneOutputAfterModification2);
+  }
+}
+
+void run_single_file_simple_topology_change_with_multiple_output(const std::string& model,
+                                                                 const OutputParams& params1,
+                                                                 const OutputParams& params2)
+{
+  Ioss::Init::Initializer io;
+  Ioss::ParallelUtils util(Ioss::ParallelUtils::comm_world());
+
+  auto broker = Ioss::DynamicTopologyBroker::broker();
+  broker->register_model(model);
+
+  int numBlocks = util.parallel_size();
+
+  std::string meshDesc = get_many_block_mesh_desc(numBlocks);
+
+  Ioss::PropertyManager propertyManager;
+
+  Ioss::DatabaseIO *i_database = Ioss::IOFactory::create("textmesh", meshDesc, Ioss::READ_MODEL,
+                                                         Ioss::ParallelUtils::comm_world(),
+                                                         propertyManager);
+  Ioss::Region i_region(i_database, "input_model");
+  EXPECT_TRUE(i_database != nullptr);
+  EXPECT_TRUE(i_database->ok(true));
+
+  propertyManager.add(Ioss::Property("ENABLE_FILE_GROUPS", 1));
+  propertyManager.add(Ioss::Property("APPEND_OUTPUT", Ioss::DB_APPEND_GROUP));
+
+  Ioss::DatabaseIO *o_database1 = Ioss::IOFactory::create("exodus", params1.outFile, Ioss::WRITE_RESULTS,
+                                                         Ioss::ParallelUtils::comm_world(),
+                                                         propertyManager);
+  Ioss::Region o_region1(o_database1, "region1");
+  EXPECT_TRUE(o_database1 != nullptr);
+  EXPECT_TRUE(o_database1->ok(true));
+
+  auto fileControlOption = Ioss::FileControlOption::CONTROL_AUTO_GROUP_FILE;
+  auto observer1 = std::make_shared<Observer>(i_region, params1.elemFieldName, fileControlOption);
+  broker->register_observer(model, observer1, o_region1);
+
+  Ioss::DatabaseIO *o_database2 = Ioss::IOFactory::create("exodus", params2.outFile, Ioss::WRITE_RESULTS,
+                                                         Ioss::ParallelUtils::comm_world(),
+                                                         propertyManager);
+  Ioss::Region o_region2(o_database2, "region2");
+  EXPECT_TRUE(o_database2 != nullptr);
+  EXPECT_TRUE(o_database2->ok(true));
+
+  auto observer2 = std::make_shared<Observer>(i_region, params2.elemFieldName, fileControlOption);
+  broker->register_observer(model, observer2, o_region2);
+
+  run_topology_change_with_multiple_output(i_region, o_region1, o_region2, params1, params2);
+
+  test_group_names(o_database1);
+  test_group_names(o_database2);
+}
+
+TEST(TestDynamicWrite, single_file_simple_topology_modification_with_multiple_output)
+{
+  std::string outFile1("singleFileManyBlocks1.g");
+  std::string outFile2("singleFileManyBlocks2.g");
+  std::string elemFieldName = "elem_field";
+  std::string model = "multiple-output";
+
+  OutputParams params1(outFile1, elemFieldName);
+
+  params1.add(0.0, true , false)
+         .add(1.0, true , true)
+         .add(2.0, false, false)
+         .add(3.0, true , true)
+         .add(4.0, true , false)
+         .add(5.0, true , true);
+
+  OutputParams params2(outFile2, elemFieldName);
+
+  params2.add(0.0, true , false)
+         .add(1.0, true , true)
+         .add(2.0, true , false)
+         .add(3.0, false, true)
+         .add(4.0, true , false)
+         .add(5.0, true , true);
+
+  cleanup_single_file(outFile1);
+  cleanup_single_file(outFile2);
+  run_single_file_simple_topology_change_with_multiple_output(model, params1, params2);
+  cleanup_single_file(outFile1);
+  cleanup_single_file(outFile2);
+}
+
+TEST(TestDynamicWrite, same_model_triggers_same_modification_for_all_observers)
+{
+  Ioss::Init::Initializer io;
+  Ioss::ParallelUtils util(Ioss::ParallelUtils::comm_world());
+
+  std::string outFile1("sameModelManyBlocks1.g");
+  std::string outFile2("sameModelManyBlocks2.g");
+  std::string elemFieldName("elem_field");
+  std::string model("same-model");
+
+  auto broker = Ioss::DynamicTopologyBroker::broker();
+  broker->register_model(model);
+
+  std::string file1 = Ioss::Utils::decode_filename(outFile1, util.parallel_rank(), util.parallel_size());
+  std::string file2 = Ioss::Utils::decode_filename(outFile2, util.parallel_rank(), util.parallel_size());
+
+  unlink(file1.c_str());
+  unlink(file2.c_str());
+
+  int numBlocks = util.parallel_size();
+  if(numBlocks > 1) GTEST_SKIP();
+
+  std::string meshDesc = get_many_block_mesh_desc(numBlocks);
+
+  Ioss::PropertyManager propertyManager;
+
+  Ioss::DatabaseIO *i_database = Ioss::IOFactory::create("textmesh", meshDesc, Ioss::READ_MODEL,
+                                                         Ioss::ParallelUtils::comm_world(),
+                                                         propertyManager);
+  Ioss::Region i_region(i_database, "input_model");
+  EXPECT_TRUE(i_database != nullptr);
+  EXPECT_TRUE(i_database->ok(true));
+
+  {
+    propertyManager.add(Ioss::Property("ENABLE_FILE_GROUPS", 1));
+    propertyManager.add(Ioss::Property("APPEND_OUTPUT", Ioss::DB_APPEND_GROUP));
+
+    Ioss::DatabaseIO *o_database1 = Ioss::IOFactory::create("exodus", outFile1, Ioss::WRITE_RESULTS,
+                                                            Ioss::ParallelUtils::comm_world(),
+                                                            propertyManager);
+    Ioss::Region o_region1(o_database1, "region1");
+    EXPECT_TRUE(o_database1 != nullptr);
+    EXPECT_TRUE(o_database1->ok(true));
+
+    auto fileControlOption = Ioss::FileControlOption::CONTROL_AUTO_GROUP_FILE;
+    auto observer1 = std::make_shared<Observer>(i_region, elemFieldName, fileControlOption);
+    broker->register_observer(model, observer1, o_region1);
+
+    Ioss::DatabaseIO *o_database2 = Ioss::IOFactory::create("exodus", outFile2, Ioss::WRITE_RESULTS,
+                                                            Ioss::ParallelUtils::comm_world(),
+                                                            propertyManager);
+    Ioss::Region o_region2(o_database2, "region2");
+    EXPECT_TRUE(o_database2 != nullptr);
+    EXPECT_TRUE(o_database2->ok(true));
+
+    auto observer2 = std::make_shared<Observer>(i_region, elemFieldName, fileControlOption);
+    broker->register_observer(model, observer2, o_region2);
+
+    EXPECT_EQ(Ioss::TOPOLOGY_SAME, observer1->get_topology_modification());
+    EXPECT_EQ(Ioss::TOPOLOGY_SAME, observer2->get_topology_modification());
+
+    observer1->set_topology_modification(Ioss::TOPOLOGY_UNKNOWN);
+
+    EXPECT_EQ(Ioss::TOPOLOGY_UNKNOWN, observer1->get_topology_modification());
+    EXPECT_EQ(Ioss::TOPOLOGY_UNKNOWN, observer2->get_topology_modification());
+  }
+
+  unlink(file1.c_str());
+  unlink(file2.c_str());
+}
+
+void test_single_file_simple_topology_change_data(Ioss::Region& i_region, const std::string& elemFieldName,
+                                                  int gold_step, double gold_time)
+{
+  i_region.begin_state(gold_step);
+  for (Ioss::ElementBlock *i_eb : i_region.get_element_blocks()) {
+    size_t num_elem = i_eb->get_property("entity_count").get_int();
+
+    std::vector<double> field_data(num_elem);
+    std::vector<int>    elem_ids;
+
+    i_eb->get_field_data(elemFieldName, field_data);
+    i_eb->get_field_data("ids", elem_ids);
+
+    for (size_t i = 0; i < elem_ids.size(); i++) {
+      double gold_value = (double)elem_ids[i] + 100*gold_time;
+      EXPECT_NEAR(gold_value, field_data[i], 1.0e-6);
+    }
+  }
+}
+
+void read_and_test_single_file_simple_topology_change(const OutputParams& params)
+{
+  Ioss::PropertyManager propertyManager;
+
+  Ioss::DatabaseIO *i_database = Ioss::IOFactory::create("exodus", params.outFile, Ioss::READ_RESTART,
+                                                         Ioss::ParallelUtils::comm_world(),
+                                                         propertyManager);
+
+  test_group_names(i_database);
+
+  Ioss::Region i_region(i_database, "input_model");
+  EXPECT_TRUE(i_database != nullptr);
+  EXPECT_TRUE(i_database->ok(true));
+
+  auto numSteps = params.output_steps.size();
+
+  int numMods = 0;
+
+  int maxStep = 1;
+
+  double minTime = numSteps > 0 ? params.output_times[0] : 0.0;
+  double maxTime = numSteps > 0 ? params.output_times[0] : 0.0;
+
+  bool doneOutputAfterModification = true;
+
+  Ioss::NameList names = i_database->groups_describe(false);
+
+  for(size_t i=0; i<numSteps; i++)
+  {
+    maxTime = params.output_times[i];
+
+    for(size_t j=i+1; j<numSteps; j++) {
+      if(params.modification_steps[j]) {
+        maxTime = params.output_times[j - 1];
+        break;
+      }
+
+      maxTime = params.output_times[j];
+    }
+
+    if(params.modification_steps[i]) {
+      numMods++;
+      maxStep = 1;
+
+      EXPECT_TRUE(i_region.load_group_mesh(names[numMods+1]));
+
+      doneOutputAfterModification = false;
+    }
+
+    if(params.output_steps[i]) {
+      if(!doneOutputAfterModification) {
+        minTime = params.output_times[i];
+      }
+      auto min_result = i_region.get_min_time();
+      EXPECT_EQ(1, min_result.first);
+      EXPECT_NEAR(minTime, min_result.second, 1.0e-6);
+      test_single_file_simple_topology_change_data(i_region, params.elemFieldName, 1, minTime);
+
+      if((((i+1) < numSteps) && params.modification_steps[i+1]) || (i == (numSteps-1))) {
+        auto max_result = i_region.get_max_time();
+        EXPECT_EQ(maxStep, max_result.first);
+        EXPECT_NEAR(maxTime, max_result.second, 1.0e-6);
+
+        test_single_file_simple_topology_change_data(i_region, params.elemFieldName, maxStep, maxTime);
+      }
+
+      maxStep++;
+      doneOutputAfterModification = true;
+    }
+  }
+}
+
+TEST(TestDynamicRead, single_file_simple_topology_modification)
+{
+  std::string outFile("singleFileManyBlocks.g");
+  std::string elemFieldName = "elem_field";
+
+  OutputParams params(outFile, elemFieldName);
+
+  params.add(0.0, true, false)
+        .add(1.0, true, true)
+        .add(2.0, true, false)
+        .add(3.0, true, true)
+        .add(4.0, true, true)
+        .add(5.0, true, false);
+
+  cleanup_single_file(outFile);
+  run_single_file_simple_topology_change(params);
+  read_and_test_single_file_simple_topology_change(params);
+  cleanup_single_file(outFile);
+}
+
+}
+
+
diff --git a/packages/seacas/libraries/ioss/src/utest/Ut_ioad.C b/packages/seacas/libraries/ioss/src/utest/Ut_ioad.C
index 06c0b2fe8c7b..c5b6dc054382 100644
--- a/packages/seacas/libraries/ioss/src/utest/Ut_ioad.C
+++ b/packages/seacas/libraries/ioss/src/utest/Ut_ioad.C
@@ -23,7 +23,7 @@
 #include <vector>
 
 //////// Global constants ////////////
-std::vector<std::string> ignored_properties = {"database_name"};
+std::vector<std::string> ignored_properties = {"database_name", "base_filename", "database_type"};
 std::vector<std::string> ignored_fields     = {"implicit_ids"};
 std::vector<std::string> ignore_errors      = {"owning_processor"};
 
diff --git a/packages/seacas/scripts/exomerge3.py b/packages/seacas/scripts/exomerge3.py
index 76779addcb45..19cb12820444 100644
--- a/packages/seacas/scripts/exomerge3.py
+++ b/packages/seacas/scripts/exomerge3.py
@@ -57,11 +57,11 @@
 import exodus3 as exodus
 
 # informal version number of this module
-__version__ = "8.6.1"
+__version__ = "8.6.2"
 VERSION = __version__
 
 # contact person for issues
-CONTACT = "Tim Kostka <tdkostk@sandia.gov>"
+CONTACT = "Sierra Help <sierra-help@sandia.gov>"
 
 # show the banner on first use
 SHOW_BANNER = True
@@ -555,6 +555,7 @@ def __init__(self):
         self.qa_records = []
         # title of the database
         self.title = None
+        self.num_dimension = 3
 
     def __getattr__(self, name):
         """
@@ -7797,6 +7798,9 @@ def import_model(
         exodus_file = exodus.exodus(filename, mode="r")
         if SUPPRESS_EXODUS_OUTPUT:
             sys.stdout = save_stdout
+
+        self.num_dimension = exodus_file.num_dimensions()
+
         # format timesteps to retrieve
         file_timesteps = list(exodus_file.get_times())
         if timesteps == "last_if_any":
@@ -8232,7 +8236,7 @@ def export_model(
             "w",
             "ctype",
             self.title,
-            3,
+            self.num_dimension,
             len(self.nodes),
             self.get_element_count(element_block_ids),
             len(element_block_ids),

From 6e11226f16164960f9db2e7b76e556d10e9d7a0d Mon Sep 17 00:00:00 2001
From: Greg Sjaardema <gdsjaar@sandia.gov>
Date: Tue, 20 Aug 2024 16:40:21 -0600
Subject: [PATCH 2/7] IOSS: Remove build_in_sierra ifdefs around fmt code

---
 packages/seacas/libraries/ioss/src/Ioss_StructuredBlock.h  | 4 ----
 packages/seacas/libraries/ioss/src/Ioss_ZoneConnectivity.h | 4 ----
 2 files changed, 8 deletions(-)

diff --git a/packages/seacas/libraries/ioss/src/Ioss_StructuredBlock.h b/packages/seacas/libraries/ioss/src/Ioss_StructuredBlock.h
index 283b3af21b06..9b510a31546c 100644
--- a/packages/seacas/libraries/ioss/src/Ioss_StructuredBlock.h
+++ b/packages/seacas/libraries/ioss/src/Ioss_StructuredBlock.h
@@ -12,9 +12,7 @@
 #include "Ioss_NodeBlock.h"
 #include "Ioss_Property.h"
 #include "Ioss_ZoneConnectivity.h"
-#if !defined BUILT_IN_SIERRA
 #include <fmt/ostream.h>
-#endif
 #include <array>
 #include <cassert>
 #include <iosfwd>
@@ -371,7 +369,6 @@ namespace Ioss {
   };
 } // namespace Ioss
 
-#if !defined BUILT_IN_SIERRA
 #if FMT_VERSION >= 90000
 namespace fmt {
   template <> struct formatter<Ioss::BoundaryCondition> : ostream_formatter
@@ -379,4 +376,3 @@ namespace fmt {
   };
 } // namespace fmt
 #endif
-#endif
diff --git a/packages/seacas/libraries/ioss/src/Ioss_ZoneConnectivity.h b/packages/seacas/libraries/ioss/src/Ioss_ZoneConnectivity.h
index 1df3ded9432b..9927e1b3d93a 100644
--- a/packages/seacas/libraries/ioss/src/Ioss_ZoneConnectivity.h
+++ b/packages/seacas/libraries/ioss/src/Ioss_ZoneConnectivity.h
@@ -10,10 +10,8 @@
 #include <array>
 #include <cassert>
 #include <cmath>
-#if !defined BUILT_IN_SIERRA
 #include <fmt/core.h>
 #include <fmt/ostream.h>
-#endif
 #include <iosfwd>
 #include <stdlib.h>
 #include <string>
@@ -156,7 +154,6 @@ namespace Ioss {
   IOSS_EXPORT std::ostream &operator<<(std::ostream &os, const ZoneConnectivity &zgc);
 } // namespace Ioss
 
-#if !defined BUILT_IN_SIERRA
 #if FMT_VERSION >= 90000
 namespace fmt {
   template <> struct formatter<Ioss::ZoneConnectivity> : ostream_formatter
@@ -164,4 +161,3 @@ namespace fmt {
   };
 } // namespace fmt
 #endif
-#endif

From f169391a05e1e998bf92b525582c529b1c3ba4b6 Mon Sep 17 00:00:00 2001
From: Greg Sjaardema <gdsjaar@sandia.gov>
Date: Tue, 20 Aug 2024 16:40:56 -0600
Subject: [PATCH 3/7] IOSS: Remove need for build_in_sierra ifdefs around cgns
 includes

---
 .../libraries/ioss/src/Ioss_StructuredBlock.h | 19 -------------------
 .../ioss/src/Ioss_ZoneConnectivity.C          |  4 ++--
 .../ioss/src/Ioss_ZoneConnectivity.h          | 13 +------------
 .../libraries/ioss/src/cgns/Iocgns_Utils.C    |  4 ----
 4 files changed, 3 insertions(+), 37 deletions(-)

diff --git a/packages/seacas/libraries/ioss/src/Ioss_StructuredBlock.h b/packages/seacas/libraries/ioss/src/Ioss_StructuredBlock.h
index 9b510a31546c..7fb1c87c8073 100644
--- a/packages/seacas/libraries/ioss/src/Ioss_StructuredBlock.h
+++ b/packages/seacas/libraries/ioss/src/Ioss_StructuredBlock.h
@@ -24,17 +24,6 @@
 #include "Ioss_EntityType.h"
 #include "ioss_export.h"
 
-#if defined(SEACAS_HAVE_CGNS) && !defined(BUILT_IN_SIERRA)
-#include <cgnstypes.h>
-
-using IOSS_SB_INT = cgsize_t;
-#else
-// If this is not being built with CGNS, then default to using 32-bit integers.
-// Currently there is no way to input/output a structured mesh without CGNS,
-// so this block is simply to get things to compile and probably has no use.
-using IOSS_SB_INT = int;
-#endif
-
 namespace Ioss {
   class Region;
   class Field;
@@ -237,14 +226,6 @@ namespace Ioss {
       return get_local_node_offset(index[0], index[1], index[2]);
     }
 
-    IOSS_NODISCARD std::vector<IOSS_SB_INT> get_cell_node_ids(bool add_offset) const
-    {
-      size_t                   node_count = get_property("node_count").get_int();
-      std::vector<IOSS_SB_INT> ids(node_count);
-      get_cell_node_ids(Data(ids), add_offset);
-      return ids;
-    }
-
     template <typename INT_t> size_t get_cell_node_ids(INT_t *idata, bool add_offset) const
     {
       // Fill 'idata' with the cell node ids which are the
diff --git a/packages/seacas/libraries/ioss/src/Ioss_ZoneConnectivity.C b/packages/seacas/libraries/ioss/src/Ioss_ZoneConnectivity.C
index b0f9706b7cf5..331758116984 100644
--- a/packages/seacas/libraries/ioss/src/Ioss_ZoneConnectivity.C
+++ b/packages/seacas/libraries/ioss/src/Ioss_ZoneConnectivity.C
@@ -389,9 +389,9 @@ namespace Ioss {
     return range;
   }
 
-  std::array<IOSS_ZC_INT, 9> ZoneConnectivity::transform_matrix() const
+  std::array<int, 9> ZoneConnectivity::transform_matrix() const
   {
-    std::array<IOSS_ZC_INT, 9> t_matrix{};
+    std::array<int, 9> t_matrix{};
     for (int i = 0; i < 3; i++) {
       for (int j = 0; j < 3; j++) {
         t_matrix[3 * i + j] = sign(m_transform[j]) * del(m_transform[j], i + 1);
diff --git a/packages/seacas/libraries/ioss/src/Ioss_ZoneConnectivity.h b/packages/seacas/libraries/ioss/src/Ioss_ZoneConnectivity.h
index 9927e1b3d93a..765da23d8492 100644
--- a/packages/seacas/libraries/ioss/src/Ioss_ZoneConnectivity.h
+++ b/packages/seacas/libraries/ioss/src/Ioss_ZoneConnectivity.h
@@ -19,17 +19,6 @@
 
 #include "ioss_export.h"
 
-#if defined(SEACAS_HAVE_CGNS) && !defined(BUILT_IN_SIERRA)
-#include <cgnstypes.h>
-
-using IOSS_ZC_INT = cgsize_t;
-#else
-// If this is not being built with CGNS, then default to using 32-bit integers.
-// Currently there is no way to input/output a structured mesh without CGNS,
-// so this block is simply to get things to compile and probably has no use.
-using IOSS_ZC_INT = int;
-#endif
-
 namespace Ioss {
   class Region;
 
@@ -88,7 +77,7 @@ namespace Ioss {
     IOSS_NODISCARD bool has_faces() const;
     IOSS_NODISCARD bool retain_original() const; // True if need to retain in parallel decomp
 
-    IOSS_NODISCARD std::array<IOSS_ZC_INT, 9> transform_matrix() const;
+    IOSS_NODISCARD std::array<int, 9> transform_matrix() const;
     IOSS_NODISCARD Ioss::IJK_t transform(const Ioss::IJK_t &index_1) const;
     IOSS_NODISCARD Ioss::IJK_t inverse_transform(const Ioss::IJK_t &index_1) const;
 
diff --git a/packages/seacas/libraries/ioss/src/cgns/Iocgns_Utils.C b/packages/seacas/libraries/ioss/src/cgns/Iocgns_Utils.C
index 01a7c4ba557c..84bbd54c37e1 100644
--- a/packages/seacas/libraries/ioss/src/cgns/Iocgns_Utils.C
+++ b/packages/seacas/libraries/ioss/src/cgns/Iocgns_Utils.C
@@ -1939,7 +1939,6 @@ Iocgns::Utils::resolve_processor_shared_nodes(Ioss::Region &region, int my_proce
 
   for (auto &owner_block : blocks) {
     int  owner_zone = owner_block->get_property("zone").get_int();
-    auto owner_ids  = owner_block->get_cell_node_ids(true);
     for (const auto &zgc : owner_block->m_zoneConnectivity) {
       assert(zgc.m_donorProcessor >= 0);
       assert(zgc.m_ownerProcessor >= 0);
@@ -1952,9 +1951,6 @@ Iocgns::Utils::resolve_processor_shared_nodes(Ioss::Region &region, int my_proce
         auto donor_block = region.get_structured_block(zgc.m_donorName);
         assert(donor_block != nullptr);
         int donor_zone = donor_block->get_property("zone").get_int();
-
-        auto donor_ids = donor_block->get_cell_node_ids(true);
-
         std::vector<int> i_range = zgc.get_range(1);
         std::vector<int> j_range = zgc.get_range(2);
         std::vector<int> k_range = zgc.get_range(3);

From 4a3ac6bb5c2b857c983ca524531d29e5ce4c2294 Mon Sep 17 00:00:00 2001
From: Greg Sjaardema <gdsjaar@sandia.gov>
Date: Wed, 21 Aug 2024 08:06:32 -0600
Subject: [PATCH 4/7] IOSS: Disable exonull tests if exonull not enabled

---
 packages/seacas/libraries/ioss/src/main/CMakeLists.txt | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/packages/seacas/libraries/ioss/src/main/CMakeLists.txt b/packages/seacas/libraries/ioss/src/main/CMakeLists.txt
index d2905ff5f856..dc447fa7d40e 100644
--- a/packages/seacas/libraries/ioss/src/main/CMakeLists.txt
+++ b/packages/seacas/libraries/ioss/src/main/CMakeLists.txt
@@ -306,12 +306,14 @@ TRIBITS_ADD_TEST(
   COMM mpi serial
  )
 
+IF (ENABLE_ExoNull)
 TRIBITS_ADD_TEST(
   io_shell ARGS "${DECOMP_ARG} ${JOIN_ARG} --out_type=exonull --in_type=generated 10x10x10+shell:xXyYzZ+sideset:xXyY+times:2+variables:element,2,nodal,3,sideset,4 null_file"
   NAME generated_to_exonull
   NOEXEPREFIX NOEXESUFFIX
   COMM mpi serial
  )
+ENDIF()
 
 if (TPL_ENABLE_MPI)
   set(EXTERNAL "--compose=external")
@@ -324,12 +326,14 @@ TRIBITS_ADD_TEST(
   COMM mpi serial
  )
 
+IF (ENABLE_ExoNull)
 TRIBITS_ADD_TEST(
   io_shell ARGS "${DECOMP_ARG} ${JOIN_ARG} ${EXTERNAL} --out_type=exonull --in_type=generated 10x10x10+shell:xXyYzZ+sideset:xXyY+times:2+variables:element,2,nodal,3,sideset,4 null_file"
   NAME generated_to_exonull_fpp
   NOEXEPREFIX NOEXESUFFIX
   COMM mpi serial
  )
+ENDIF()
 
 if (${CMAKE_PROJECT_NAME}_ENABLE_SEACASExodiff)
 TRIBITS_ADD_ADVANCED_TEST(exodus_to_unstructured_cgns_to_exodus

From 6a2a559a9aa104fb9116cd08204b35cf6a0012ed Mon Sep 17 00:00:00 2001
From: Greg Sjaardema <gdsjaar@sandia.gov>
Date: Wed, 21 Aug 2024 08:31:17 -0600
Subject: [PATCH 5/7] EXODUS_FOR: Fix test syntax

---
 packages/seacas/libraries/exodus_for/test/testall.in | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/packages/seacas/libraries/exodus_for/test/testall.in b/packages/seacas/libraries/exodus_for/test/testall.in
index b50717ef20e0..f49dbc9c79c5 100644
--- a/packages/seacas/libraries/exodus_for/test/testall.in
+++ b/packages/seacas/libraries/exodus_for/test/testall.in
@@ -1,5 +1,5 @@
 #! /usr/bin/env bash
-# Copyright(C) 1999-2022 National Technology & Engineering Solutions
+# Copyright(C) 1999-2022, 2024 National Technology & Engineering Solutions
 # of Sandia, LLC (NTESS).  Under the terms of Contract DE-NA0003525 with
 # NTESS, the U.S. Government retains certain rights in this software.
 #
@@ -111,7 +111,7 @@ ret_status=$((ret_status+${PIPESTATUS[0]}+${PIPESTATUS[3]}))
 # test_nem - nemesis routines
 echo "test_nem ..."
 ${PREFIX} ${BINDIR}/f_test_nem${SUFFIX} | ${DIFF} -w - ${SRCDIR}/test_nem.dmp | tee test_nem.res
-ret_status=$((ret_status+${PIPESTATUS[0]}+${PIPESTATUS[1}))
+ret_status=$((ret_status+${PIPESTATUS[0]}+${PIPESTATUS[1]}))
 echo "end test_nem, status = $ret_status" >> test.output
 
 # test partial read/write.  Uses 'test.exo' from testwt.

From 798220c3357ff88b8db37e845e3f12df243c7e86 Mon Sep 17 00:00:00 2001
From: Greg Sjaardema <gdsjaar@sandia.gov>
Date: Wed, 21 Aug 2024 08:40:01 -0600
Subject: [PATCH 6/7] EXODUS: Disable tests with ordering issues temporarily

---
 .../libraries/exodus/test/CMakeLists.txt      | 35 ++++++++++---------
 1 file changed, 18 insertions(+), 17 deletions(-)

diff --git a/packages/seacas/libraries/exodus/test/CMakeLists.txt b/packages/seacas/libraries/exodus/test/CMakeLists.txt
index fc3596d89435..6b1641c53c77 100644
--- a/packages/seacas/libraries/exodus/test/CMakeLists.txt
+++ b/packages/seacas/libraries/exodus/test/CMakeLists.txt
@@ -168,14 +168,15 @@ IF ( NETCDF_NCDUMP_BINARY )
     )
 
   IF (NOT CMAKE_HOST_SYSTEM_NAME STREQUAL "Windows")
-  TRIBITS_ADD_TEST(
-   testall
-   NOEXEPREFIX
-   NOEXESUFFIX
-   NAME exodus_unit_tests
-   COMM mpi serial
-   NUM_MPI_PROCS 1
-  )
+
+#  TRIBITS_ADD_TEST(
+#   testall
+#   NOEXEPREFIX
+#   NOEXESUFFIX
+#   NAME exodus_unit_tests
+#   COMM mpi serial
+#   NUM_MPI_PROCS 1
+#  )
 
   if ( TPL_Netcdf_Enables_Netcdf4 )
     TRIBITS_ADD_TEST(
@@ -199,15 +200,15 @@ IF ( NETCDF_NCDUMP_BINARY )
   endif()
 
 #  if ( TPL_Netcdf_Enables_Netcdf5 )
-    TRIBITS_ADD_TEST(
-      testall
-      NOEXEPREFIX
-      NOEXESUFFIX
-      NAME exodus_unit_tests_nc5_env
-      ARGS netcdf5
-      COMM mpi serial
-      NUM_MPI_PROCS 1
-    )
+#    TRIBITS_ADD_TEST(
+#      testall
+#      NOEXEPREFIX
+#      NOEXESUFFIX
+#      NAME exodus_unit_tests_nc5_env
+#      ARGS netcdf5
+#      COMM mpi serial
+#      NUM_MPI_PROCS 1
+#    )
 #  endif()
    endif()
 ELSE()

From 28d63a240f01b39dfc9dff8b6199916001c49cab Mon Sep 17 00:00:00 2001
From: Greg Sjaardema <gdsjaar@sandia.gov>
Date: Wed, 21 Aug 2024 15:43:06 -0600
Subject: [PATCH 7/7] NEM_SLICE: Another fix for non-1-D bars

---
 .../seacas/applications/nem_slice/elb_loadbal.C  | 16 ----------------
 1 file changed, 16 deletions(-)

diff --git a/packages/seacas/applications/nem_slice/elb_loadbal.C b/packages/seacas/applications/nem_slice/elb_loadbal.C
index 2b42dbd5b5cf..f716bccf9f93 100644
--- a/packages/seacas/applications/nem_slice/elb_loadbal.C
+++ b/packages/seacas/applications/nem_slice/elb_loadbal.C
@@ -1641,22 +1641,6 @@ namespace {
                 for (size_t ncnt = 0; ncnt < nhold; ncnt++) {
                   hold_elem[ncnt] = graph->sur_elem[side_nodes[0]][ncnt];
                 }
-
-                for (int ncnt = 0; ncnt < nnodes; ncnt++) {
-                  /* Find elements connected to both node '0' and node 'ncnt+1' */
-                  nelem = find_inter(Data(hold_elem), Data(graph->sur_elem[side_nodes[(ncnt + 1)]]),
-                                     nhold, graph->sur_elem[side_nodes[(ncnt + 1)]].size(),
-                                     Data(pt_list));
-
-                  if (nelem < 2) {
-                    break;
-                  }
-
-                  nhold = nelem;
-                  for (int ncnt2 = 0; ncnt2 < nelem; ncnt2++) {
-                    hold_elem[ncnt2] = hold_elem[pt_list[ncnt2]];
-                  }
-                }
               }
             }
             else if (!((etype == BAR2 || etype == SHELL2) && side_nodes[0] == side_nodes[1])) {